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 (
    9809, 9810, 9811, 9812, 9807, 9808, 10455, 
    10456, 10454, 10453, 10452, 10451, 
    10450, 10449, 10448, 10447, 12691, 
    12692, 12693, 12694
  ) 
  AND cscart_product_descriptions.lang_code = 'ru'

Query time 0.00049

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "product_id"],
      "key": "PRIMARY",
      "key_length": "9",
      "used_key_parts": ["product_id", "lang_code"],
      "rows": 20,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (9809,9810,9811,9812,9807,9808,10455,10456,10454,10453,10452,10451,10450,10449,10448,10447,12691,12692,12693,12694) and cscart_product_descriptions.lang_code = 'ru'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text unit_name
9807 <p>Коллекция GENERATION на НТВ в "Дачный Ответ"</p><p><iframe width="100%" height="400" src="https://www.youtube.com/embed/4d4JYmzzj5I" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen=""></iframe></p>
9808 <p>Коллекция GENERATION на НТВ в "Дачный Ответ"</p><p><iframe width="100%" height="400" src="https://www.youtube.com/embed/4d4JYmzzj5I" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen=""></iframe></p>
9809 <p>Коллекция GENERATION на НТВ в "Дачный Ответ"</p><p><iframe width="100%" height="400" src="https://www.youtube.com/embed/4d4JYmzzj5I" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen=""></iframe></p>
9810 <p>Коллекция GENERATION на НТВ в "Дачный Ответ"</p><p><iframe width="100%" height="400" src="https://www.youtube.com/embed/4d4JYmzzj5I" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen=""></iframe></p>
9811 <p>Коллекция GENERATION на НТВ в "Дачный Ответ"</p><p><iframe width="100%" height="400" src="https://www.youtube.com/embed/4d4JYmzzj5I" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen=""></iframe></p>
9812 <p>Коллекция GENERATION на НТВ в "Дачный Ответ"</p><p><iframe width="100%" height="400" src="https://www.youtube.com/embed/4d4JYmzzj5I" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen=""></iframe></p>
10447
10448
10449
10450
10451
10452
10453
10454
10455
10456
12691
12692
12693
12694