SELECT 
  product_id, 
  feature_short_desc 
FROM 
  cscart_ab__short_desc_from_features_values 
WHERE 
  product_id IN (
    21181, 21182, 21183, 21184, 21185, 21186, 
    21187, 21188, 21189, 21190, 21191, 
    21192, 21193, 21194, 21195, 21196
  ) 
  AND lang_code = 'ru' 
  AND storefront_id = 1

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_ab__short_desc_from_features_values",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "9",
      "used_key_parts": ["product_id", "lang_code"],
      "rows": 32,
      "filtered": 100,
      "attached_condition": "cscart_ab__short_desc_from_features_values.storefront_id = 1 and cscart_ab__short_desc_from_features_values.product_id in (21181,21182,21183,21184,21185,21186,21187,21188,21189,21190,21191,21192,21193,21194,21195,21196) and cscart_ab__short_desc_from_features_values.lang_code = 'ru'"
    }
  }
}