SELECT 
  cscart_bm_snapping.grid_id as grid_id, 
  cscart_bm_snapping.block_id as block_id, 
  IFNULL(
    dynamic_object_content.content, 
    default_content.content
  ) as content, 
  IFNULL(
    dynamic_object_content.object_id, 
    default_content.object_id
  ) AS object_id, 
  IFNULL(
    dynamic_object_content.object_type, 
    default_content.object_type
  ) AS object_type, 
  cscart_bm_block_statuses.object_ids as object_ids, 
  cscart_bm_snapping.*, 
  cscart_bm_blocks.*, 
  cscart_bm_blocks_descriptions.* 
FROM 
  cscart_bm_snapping 
  LEFT JOIN cscart_bm_blocks ON cscart_bm_blocks.block_id = cscart_bm_snapping.block_id 
  LEFT JOIN cscart_bm_block_statuses ON cscart_bm_snapping.snapping_id = cscart_bm_block_statuses.snapping_id 
  AND cscart_bm_block_statuses.object_type LIKE '' 
  LEFT JOIN cscart_bm_blocks_descriptions ON cscart_bm_blocks.block_id = cscart_bm_blocks_descriptions.block_id 
  LEFT JOIN cscart_bm_blocks_content AS default_content ON cscart_bm_blocks.block_id = default_content.block_id 
  AND cscart_bm_blocks_descriptions.lang_code = default_content.lang_code 
  AND default_content.snapping_id = 0 
  AND default_content.object_id = 0 
  AND default_content.object_type like '' 
  LEFT JOIN cscart_bm_blocks_content AS dynamic_object_content ON cscart_bm_blocks.block_id = dynamic_object_content.block_id 
  AND cscart_bm_blocks_descriptions.lang_code = dynamic_object_content.lang_code 
  AND dynamic_object_content.object_id = 0 
  AND dynamic_object_content.object_type like '' 
WHERE 
  cscart_bm_snapping.grid_id IN (45, 46, 47, 48, 49, 50, 51) 
  AND cscart_bm_blocks_descriptions.lang_code = 'en' 
ORDER BY 
  cscart_bm_snapping.order, 
  cscart_bm_snapping.block_id

Query time 0.00255

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "109.53"
    },
    "ordering_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "22.68"
      },
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_bm_blocks_descriptions",
            "access_type": "ALL",
            "possible_keys": [
              "PRIMARY"
            ],
            "rows_examined_per_scan": 63,
            "rows_produced_per_join": 6,
            "filtered": "10.00",
            "cost_info": {
              "read_cost": "13.76",
              "eval_cost": "1.26",
              "prefix_cost": "15.02",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "block_id",
              "lang_code",
              "name"
            ],
            "attached_condition": "(`satishecarter_march_003`.`cscart_bm_blocks_descriptions`.`lang_code` = 'en')"
          }
        },
        {
          "table": {
            "table_name": "cscart_bm_blocks",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "block_id"
            ],
            "key_length": "4",
            "ref": [
              "satishecarter_march_003.cscart_bm_blocks_descriptions.block_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 6,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "6.30",
              "eval_cost": "1.26",
              "prefix_cost": "22.58",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "block_id",
              "type",
              "properties",
              "company_id",
              "storefront_id"
            ]
          }
        },
        {
          "table": {
            "table_name": "default_content",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "block_id",
              "snapping_id",
              "lang_code",
              "object_id"
            ],
            "key_length": "18",
            "ref": [
              "satishecarter_march_003.cscart_bm_blocks_descriptions.block_id",
              "const",
              "satishecarter_march_003.cscart_bm_blocks_descriptions.lang_code",
              "const"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 6,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "6.30",
              "eval_cost": "1.26",
              "prefix_cost": "30.14",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "snapping_id",
              "object_id",
              "object_type",
              "block_id",
              "lang_code",
              "content"
            ],
            "attached_condition": "<if>(is_not_null_compl(default_content), (`satishecarter_march_003`.`default_content`.`object_type` like ''), true)"
          }
        },
        {
          "table": {
            "table_name": "dynamic_object_content",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "block_id"
            ],
            "key_length": "4",
            "ref": [
              "satishecarter_march_003.cscart_bm_blocks_descriptions.block_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 6,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "6.30",
              "eval_cost": "1.26",
              "prefix_cost": "37.70",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "object_id",
              "object_type",
              "block_id",
              "lang_code",
              "content"
            ],
            "attached_condition": "<if>(is_not_null_compl(dynamic_object_content), ((`satishecarter_march_003`.`dynamic_object_content`.`object_id` = 0) and (`satishecarter_march_003`.`dynamic_object_content`.`lang_code` = `satishecarter_march_003`.`cscart_bm_blocks_descriptions`.`lang_code`) and (`satishecarter_march_003`.`dynamic_object_content`.`object_type` like '')), true)"
          }
        },
        {
          "table": {
            "table_name": "cscart_bm_snapping",
            "access_type": "ALL",
            "possible_keys": [
              "grid_id"
            ],
            "rows_examined_per_scan": 99,
            "rows_produced_per_join": 11,
            "filtered": "1.82",
            "using_join_buffer": "Block Nested Loop",
            "cost_info": {
              "read_cost": "19.75",
              "eval_cost": "2.27",
              "prefix_cost": "80.12",
              "data_read_per_join": "8K"
            },
            "used_columns": [
              "snapping_id",
              "block_id",
              "grid_id",
              "wrapper",
              "user_class",
              "order",
              "status"
            ],
            "attached_condition": "((`satishecarter_march_003`.`cscart_bm_snapping`.`block_id` = `satishecarter_march_003`.`cscart_bm_blocks_descriptions`.`block_id`) and (`satishecarter_march_003`.`cscart_bm_snapping`.`grid_id` in (45,46,47,48,49,50,51)))"
          }
        },
        {
          "table": {
            "table_name": "cscart_bm_block_statuses",
            "access_type": "ALL",
            "possible_keys": [
              "snapping_id"
            ],
            "rows_examined_per_scan": 2,
            "rows_produced_per_join": 22,
            "filtered": "100.00",
            "using_join_buffer": "Block Nested Loop",
            "cost_info": {
              "read_cost": "2.19",
              "eval_cost": "4.54",
              "prefix_cost": "86.85",
              "data_read_per_join": "2K"
            },
            "used_columns": [
              "snapping_id",
              "object_ids",
              "object_type"
            ],
            "attached_condition": "<if>(is_not_null_compl(cscart_bm_block_statuses), ((`satishecarter_march_003`.`cscart_bm_snapping`.`snapping_id` = `satishecarter_march_003`.`cscart_bm_block_statuses`.`snapping_id`) and (`satishecarter_march_003`.`cscart_bm_block_statuses`.`object_type` like '')), true)"
          }
        }
      ]
    }
  }
}

Result

grid_id block_id content object_id object_type object_ids snapping_id wrapper user_class order status type properties company_id storefront_id lang_code name
50 5 0 54 top-logo 0 A template a:2:{s:8:"template";s:32:"blocks/static_templates/logo.tpl";s:11:"enable_link";s:1:"Y";} 0 1 en Logo
46 32 0 39 0 A template a:2:{s:8:"template";s:32:"blocks/static_templates/logo.tpl";s:11:"enable_link";s:1:"N";} 0 1 en Logo without link
47 33 a:1:{s:5:"items";a:3:{s:7:"filling";s:8:"manually";s:8:"item_ids";s:8:"23,25,27";s:8:"required";a:3:{s:11:"field_id_23";s:1:"N";s:11:"field_id_25";s:1:"N";s:11:"field_id_27";s:1:"N";}}} 0 40 0 A lite_checkout_location a:1:{s:8:"template";s:33:"blocks/lite_checkout/location.tpl";} 0 1 en Deliver to
48 43 0 51 blocks/wrappers/sidebox_important.tpl ty-carts-summary 0 A carts_summary a:1:{s:8:"template";s:47:"addons/direct_payments/blocks/carts_summary.tpl";} 0 1 en Carts summary
48 44 0 52 order-products 0 A checkout a:1:{s:8:"template";s:36:"blocks/checkout/products_in_cart.tpl";} 0 1 en Products in your order
47 34 0 41 1 A lite_checkout_shipping_methods a:2:{s:8:"template";s:41:"blocks/lite_checkout/shipping_methods.tpl";s:40:"show_vendor_info_if_shipping_no_required";s:1:"Y";} 0 1 en Shipping methods
48 45 0 53 1 A checkout a:1:{s:8:"template";s:27:"blocks/checkout/summary.tpl";} 0 1 en Order summary
51 18 0 55 2 A template a:1:{s:8:"template";s:37:"blocks/static_templates/copyright.tpl";} 0 1 en Copyright
47 35 0 42 2 A lite_checkout_customer_sign_in a:1:{s:8:"template";s:41:"blocks/lite_checkout/customer_sign_in.tpl";} 0 1 en Customer
47 36 a:1:{s:5:"items";a:3:{s:7:"filling";s:8:"manually";s:8:"item_ids";s:5:"19,29";s:8:"required";a:2:{s:11:"field_id_19";s:1:"Y";s:11:"field_id_29";s:1:"Y";}}} 0 43 3 A lite_checkout_customer_address a:1:{s:8:"template";s:41:"blocks/lite_checkout/customer_address.tpl";} 0 1 en Address
47 37 a:1:{s:5:"items";a:3:{s:7:"filling";s:8:"manually";s:8:"item_ids";s:8:"6,7,9,32";s:8:"required";a:4:{s:10:"field_id_6";s:1:"N";s:10:"field_id_7";s:1:"N";s:10:"field_id_9";s:1:"N";s:11:"field_id_32";s:1:"Y";}}} 0 44 4 A lite_checkout_customer_information a:1:{s:8:"template";s:45:"blocks/lite_checkout/customer_information.tpl";} 0 1 en Customer information
47 38 0 45 5 A lite_checkout_customer_notes a:1:{s:8:"template";s:39:"blocks/lite_checkout/customer_notes.tpl";} 0 1 en Customer's notes
47 39 0 46 blocks/lite_checkout/wrappers/checkout_block_with_heading.tpl 6 A lite_checkout_payment_methods a:1:{s:8:"template";s:40:"blocks/lite_checkout/payment_methods.tpl";} 0 1 en Payment methods
47 40 a:1:{s:5:"items";a:3:{s:7:"filling";s:8:"manually";s:8:"item_ids";s:23:"14,16,30,18,28,22,24,26";s:8:"required";a:8:{s:11:"field_id_14";s:1:"N";s:11:"field_id_16";s:1:"N";s:11:"field_id_30";s:1:"N";s:11:"field_id_18";s:1:"N";s:11:"field_id_28";s:1:"N";s:11:"field_id_22";s:1:"N";s:11:"field_id_24";s:1:"N";s:11:"field_id_26";s:1:"N";}}} 0 47 7 A lite_checkout_customer_billing a:1:{s:8:"template";s:41:"blocks/lite_checkout/customer_billing.tpl";} 0 1 en Billing address
47 41 0 48 8 A lite_checkout_terms_and_conditions a:1:{s:8:"template";s:45:"blocks/lite_checkout/terms_and_conditions.tpl";} 0 1 en Terms and conditions
47 42 0 49 9 A lite_checkout_newsletters a:1:{s:8:"template";s:55:"addons/newsletters/blocks/lite_checkout/newsletters.tpl";} 0 1 en Sign up for our newsletters!
47 11 0 50 blocks/wrappers/mainbox_general.tpl 10 D main 0 1 en Main Content