SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_destination_products_amount 
WHERE 
  product_id IN (
    20589, 20590, 20669, 20597, 20595, 20593, 
    20594, 20693, 20596, 20672, 20670, 
    20671, 20614, 20615, 20616, 20673, 
    20617, 20618, 20600, 20715, 20602, 
    20716, 20694, 20717
  ) 
  AND destination_id = 115 
  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": 24,
      "filtered": 75,
      "index_condition": "cscart_warehouses_destination_products_amount.destination_id = 115 and cscart_warehouses_destination_products_amount.storefront_id = 0 and cscart_warehouses_destination_products_amount.product_id in (20589,20590,20669,20597,20595,20593,20594,20693,20596,20672,20670,20671,20614,20615,20616,20673,20617,20618,20600,20715,20602,20716,20694,20717)"
    }
  }
}