SELECT 
  cscart_product_descriptions.product_id, 
  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 (
    10792, 10793, 10794, 10795, 10796, 10797, 
    10798, 10799, 10800, 10801, 10802, 
    10803, 10805, 10806, 10807, 10808, 
    10809, 10810, 10811, 10812
  ) 
  AND cscart_product_descriptions.lang_code = 'ru'

Query time 0.00090

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 (10792,10793,10794,10795,10796,10797,10798,10799,10800,10801,10802,10803,10805,10806,10807,10808,10809,10810,10811,10812) and cscart_product_descriptions.lang_code = 'ru'"
    }
  }
}