SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '' 
    OR cscart_product_descriptions.short_description IS NULL, 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    93287, 93288, 93289, 93290, 93291, 93294, 
    93338, 93339, 93341, 93342, 93343, 
    93344, 93345, 93346, 93347, 93348, 
    93349, 93350, 93351, 93352, 93353, 
    93354, 93355, 93356, 93357, 93358, 
    93750, 93751, 93752, 93753
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "13.52"
    },
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 30,
      "rows_produced_per_join": 30,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "10.52",
        "eval_cost": "3.00",
        "prefix_cost": "13.52",
        "data_read_per_join": "114K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (93287,93288,93289,93290,93291,93294,93338,93339,93341,93342,93343,93344,93345,93346,93347,93348,93349,93350,93351,93352,93353,93354,93355,93356,93357,93358,93750,93751,93752,93753)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
93287
93288
93289
93290
93291
93294
93338
93339
93341
93342
93343
93344
93345
93346
93347
93348
93349
93350
93351
93352
93353
93354
93355
93356
93357
93358
93750
93751
93752
93753