SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_sum_products_amount 
WHERE 
  1 
  AND product_id IN (
    5405, 5236, 4613, 4614, 4615, 4616, 5212, 
    5043, 5213, 4775, 4776, 5364, 5365, 
    5366, 5403, 5370, 5329, 5237, 5238, 
    5436, 5239, 5240, 5437, 5438
  )

Query time 0.00086

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": 26,
      "filtered": 100,
      "index_condition": "cscart_warehouses_sum_products_amount.product_id in (5405,5236,4613,4614,4615,4616,5212,5043,5213,4775,4776,5364,5365,5366,5403,5370,5329,5237,5238,5436,5239,5240,5437,5438)"
    }
  }
}