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, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    114, 115, 116, 117, 210, 211, 212, 213, 
    214, 215, 216, 217, 218, 219, 220, 221, 
    222, 223, 278, 279, 280, 281, 282, 283, 
    284, 332, 333, 334, 335, 336, 337, 3915, 
    3916, 3917, 3918, 3919, 3920, 3921, 
    3968, 3969, 3970, 3971, 3972, 3973, 
    3974, 4020, 4021, 4022
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00093

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "57.81"
    },
    "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": 48,
      "rows_produced_per_join": 48,
      "filtered": "100.00",
      "index_condition": "((`gaseus`.`cscart_product_descriptions`.`product_id` in (114,115,116,117,210,211,212,213,214,215,216,217,218,219,220,221,222,223,278,279,280,281,282,283,284,332,333,334,335,336,337,3915,3916,3917,3918,3919,3920,3921,3968,3969,3970,3971,3972,3973,3974,4020,4021,4022)) and (`gaseus`.`cscart_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "53.01",
        "eval_cost": "4.80",
        "prefix_cost": "57.81",
        "data_read_per_join": "219K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "meta_keywords",
        "meta_description",
        "search_words",
        "promo_text",
        "unit_name"
      ]
    }
  }
}