SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_sum_products_amount 
WHERE 
  1 
  AND product_id IN (
    51547, 51551, 51540, 51545, 51541, 51550, 
    51543, 51542, 51544, 51546, 51548
  )

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.61"
    },
    "table": {
      "table_name": "cscart_warehouses_sum_products_amount",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 33,
      "rows_produced_per_join": 33,
      "filtered": "100.00",
      "index_condition": "(`test_uchur_k`.`cscart_warehouses_sum_products_amount`.`product_id` in (51547,51551,51540,51545,51541,51550,51543,51542,51544,51546,51548))",
      "cost_info": {
        "read_cost": "14.31",
        "eval_cost": "3.30",
        "prefix_cost": "17.61",
        "data_read_per_join": "528"
      },
      "used_columns": [
        "product_id",
        "amount"
      ]
    }
  }
}

Result

product_id amount
51540 3
51540 3
51541 3
51541 3
51542 3
51542 3
51543 3
51543 3
51544 2
51544 2
51545 2
51545 2
51546 2
51546 2
51547 10
51547 10
51548 9
51548 9
51550 4
51550 4
51551 3
51551 3