SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_destination_products_amount 
WHERE 
  product_id IN (
    12669, 12975, 2299, 2297, 2298, 2203, 
    2566, 3215, 3214, 11118, 12685, 13990, 
    2340, 11888, 2339, 2338, 2180, 2181, 
    13661, 15141, 2228, 2226, 2227, 2336, 
    12743, 2185, 14298, 15154, 13222, 15155
  ) 
  AND destination_id = 12 
  AND storefront_id = 0

Query time 0.00057

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_warehouses_destination_products_amount",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "idx_storefront_id"],
      "key": "PRIMARY",
      "key_length": "9",
      "used_key_parts": ["product_id", "destination_id", "storefront_id"],
      "rows": 30,
      "filtered": 100,
      "index_condition": "cscart_warehouses_destination_products_amount.destination_id = 12 and cscart_warehouses_destination_products_amount.storefront_id = 0 and cscart_warehouses_destination_products_amount.product_id in (12669,12975,2299,2297,2298,2203,2566,3215,3214,11118,12685,13990,2340,11888,2339,2338,2180,2181,13661,15141,2228,2226,2227,2336,12743,2185,14298,15154,13222,15155)"
    }
  }
}