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 (
    89, 1643, 1645, 1925, 1666, 1664, 1557, 
    1695, 1559, 1315, 1310, 1471, 1502, 
    86, 1504, 33, 1944, 1942, 1900, 1433, 
    1777, 1748, 1679, 1702
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00052

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": 24,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (89,1643,1645,1925,1666,1664,1557,1695,1559,1315,1310,1471,1502,86,1504,33,1944,1942,1900,1433,1777,1748,1679,1702) and cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text unit_name
33
86
89
1310
1315
1433
1471
1502
1504
1557
1559
1643
1645
1664
1666
1679
1695
1702
1748
1777
1900
1925
1942
1944