ซึ่งถ้าทำความเข้าใจกันได้ตรงระหว่างผู้ซื้อและผู้ขายก็หมดปัญหาthe management of customers' needs, it should consider the principle of "What you paid is what you get
If you understand exactly between buyers and sellers is a problem the management of customers' needs, it should consider the principle of "What you paid is what you get.