SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    10082, 10081, 10080, 10079, 10584, 10594, 
    9814, 9815, 9816, 9817, 9818, 15732, 
    9820, 9821, 9822, 9823
  )

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_products",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 16,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (10082,10081,10080,10079,10584,10594,9814,9815,9816,9817,9818,15732,9820,9821,9822,9823)"
    }
  }
}