SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_sum_products_amount 
WHERE 
  1 
  AND product_id IN (
    4843, 4835, 4824, 4438, 5073, 4828, 4359, 
    4360, 4422, 4440, 4446, 4629, 4625, 
    4886, 4485, 4768, 4781, 4829, 4784, 
    18144, 4785, 5348, 4970, 4802
  )

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_warehouses_sum_products_amount",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 32,
      "filtered": 100,
      "index_condition": "cscart_warehouses_sum_products_amount.product_id in (4843,4835,4824,4438,5073,4828,4359,4360,4422,4440,4446,4629,4625,4886,4485,4768,4781,4829,4784,18144,4785,5348,4970,4802)"
    }
  }
}

Result

product_id amount
4359 1
4360 2
4422 1
4438 1
4440 1
4446 1
4485 9
4625 6
4629 3
4768 7
4781 2
4784 4
4785 2
4802 2
4824 1
4828 2
4829 2
4835 1
4843 1
4886 1
4970 3
5073 1
5348 1
18144 6