SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_sum_products_amount 
WHERE 
  1 
  AND product_id IN (
    121, 119, 141, 23, 4, 142, 120, 62, 108, 
    107, 94, 8, 86, 54, 10, 93
  )

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.06"
    },
    "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": 29,
      "rows_produced_per_join": 29,
      "filtered": "100.00",
      "index_condition": "(`test_uchur_k`.`cscart_warehouses_sum_products_amount`.`product_id` in (121,119,141,23,4,142,120,62,108,107,94,8,86,54,10,93))",
      "cost_info": {
        "read_cost": "14.16",
        "eval_cost": "2.90",
        "prefix_cost": "17.06",
        "data_read_per_join": "464"
      },
      "used_columns": [
        "product_id",
        "amount"
      ]
    }
  }
}

Result

product_id amount
4 15
4 15
8 3
8 3
10 38
10 38
23 19
23 19
54 3
54 3
62 20
62 20
86 27
86 27
93 1
93 1
94 1
94 1
107 17
107 17
108 10
108 10
119 27
119 27
120 25
120 25
121 22
121 22
141 11
141 11
142 12
142 12