SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    6313, 6312, 6315, 6237, 6308, 6314, 6307, 
    6309, 6311, 6310
  )

Query time 0.00031

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": 10,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (6313,6312,6315,6237,6308,6314,6307,6309,6311,6310)"
    }
  }
}