SELECT 
  product_id, 
  feature_short_desc 
FROM 
  cscart_ab__short_desc_from_features_values 
WHERE 
  product_id IN (
    20749, 20750, 20751, 20752, 20753, 20754, 
    20755, 20756, 20757, 20758, 20759, 
    20760, 20761, 20762, 20763, 20764
  ) 
  AND lang_code = 'en' 
  AND storefront_id = 1

Query time 0.00021

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": 16,
      "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 (20749,20750,20751,20752,20753,20754,20755,20756,20757,20758,20759,20760,20761,20762,20763,20764) and cscart_ab__short_desc_from_features_values.lang_code = 'en'"
    }
  }
}