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 (
    93281, 93282, 93283, 93284, 93285, 93286, 
    93287, 93288, 93289, 93290, 93291, 
    93294, 93338, 93339, 93359, 93360, 
    93361, 93523, 93524, 93525, 93526, 
    93527, 93528, 93781, 93782, 93783, 
    93784, 93785, 93786, 94026
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00087

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 (93281,93282,93283,93284,93285,93286,93287,93288,93289,93290,93291,93294,93338,93339,93359,93360,93361,93523,93524,93525,93526,93527,93528,93781,93782,93783,93784,93785,93786,94026)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
93281
93282
93283
93284
93285
93286
93287
93288
93289
93290
93291
93294
93338
93339
93359
93360
93361
93523
93524
93525
93526
93527
93528
93781
93782
93783
93784
93785
93786
94026