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 (
    51514, 51520, 51538, 51468, 51476, 51503, 
    51541, 51492, 51513, 51522, 51539, 
    51491, 51499, 51474, 51515, 51502, 
    51519, 51466, 51518, 51509, 51508, 
    51485, 51550, 51465, 51524, 51528, 
    51504, 51512, 51527, 51511, 51482, 
    51046
  ) 
  AND cscart_product_descriptions.lang_code = 'kk'

Query time 0.00093

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "22.41"
    },
    "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": 32,
      "rows_produced_per_join": 32,
      "filtered": "100.00",
      "index_condition": "((`test_uchur_k`.`cscart_product_descriptions`.`product_id` in (51514,51520,51538,51468,51476,51503,51541,51492,51513,51522,51539,51491,51499,51474,51515,51502,51519,51466,51518,51509,51508,51485,51550,51465,51524,51528,51504,51512,51527,51511,51482,51046)) and (`test_uchur_k`.`cscart_product_descriptions`.`lang_code` = 'kk'))",
      "cost_info": {
        "read_cost": "19.21",
        "eval_cost": "3.20",
        "prefix_cost": "22.41",
        "data_read_per_join": "146K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "meta_keywords",
        "meta_description",
        "search_words",
        "promo_text",
        "unit_name"
      ]
    }
  }
}