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 (
    9776, 9781, 9775, 9778, 9779, 9780, 9782, 
    9790, 9787, 9791, 9792, 9795, 9784, 
    9785, 9783, 9786, 9788
  ) 
  AND cscart_product_descriptions.lang_code = 'ru'

Query time 0.00048

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": 17,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (9776,9781,9775,9778,9779,9780,9782,9790,9787,9791,9792,9795,9784,9785,9783,9786,9788) and cscart_product_descriptions.lang_code = 'ru'"
    }
  }
}