SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.short_description, 
  cscart_product_descriptions.full_description, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.page_title, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    13445, 13446, 13447, 13448, 15166, 15732, 
    18508, 13504, 13449, 14651, 14140, 
    13450, 13946, 13916, 13963, 13919, 
    13929, 13932, 13895, 14020, 14656, 
    14654, 14661, 13899
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.04252208,
    "nested_loop": [
      {
        "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"],
          "loops": 1,
          "rows": 24,
          "cost": 0.04252208,
          "filtered": 100,
          "attached_condition": "cscart_product_descriptions.product_id in (13445,13446,13447,13448,15166,15732,18508,13504,13449,14651,14140,13450,13946,13916,13963,13919,13929,13932,13895,14020,14656,14654,14661,13899) and cscart_product_descriptions.lang_code = 'en'"
        }
      }
    ]
  }
}