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 (
    94453, 94454, 94455, 94456, 94458, 94459, 
    94460, 94461, 94462, 94751, 94752, 
    94753, 94754, 94755, 94756, 94757, 
    94758, 94762, 94764, 95565, 95567, 
    95568, 95570, 95572
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00070

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "10.82"
    },
    "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": 24,
      "rows_produced_per_join": 24,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "8.42",
        "eval_cost": "2.40",
        "prefix_cost": "10.82",
        "data_read_per_join": "91K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (94453,94454,94455,94456,94458,94459,94460,94461,94462,94751,94752,94753,94754,94755,94756,94757,94758,94762,94764,95565,95567,95568,95570,95572)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
94453
94454
94455
94456
94458
94459
94460
94461
94462
94751
94752
94753
94754
94755
94756
94757
94758
94762
94764
95565
95567
95568
95570
95572