SELECT 
  product_id, 
  feature_short_desc 
FROM 
  cscart_ab__short_desc_from_features_values 
WHERE 
  product_id IN (
    21967, 21968, 21969, 21970, 21971, 21972, 
    21973, 21974, 21975, 21976, 21977, 
    21978, 21979, 21980, 21981, 21982
  ) 
  AND lang_code = 'ru' 
  AND storefront_id = 1

Query time 0.00030

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 (21967,21968,21969,21970,21971,21972,21973,21974,21975,21976,21977,21978,21979,21980,21981,21982) and cscart_ab__short_desc_from_features_values.lang_code = 'ru'"
    }
  }
}