Perhaps you should try some spelling variations:
dung phuong » dung thuong, bang phuong, dung chung
thanh trung » thanh tung
hieu lang » chieu sang, hieu quang, nhieu tang
doan toan » doan tuan, doanh hoan, doan trang
trung va » truong va, trang va, trung ha
dan toan » van toan, dan than, manh toan
ho hieu » ho chieu, hoi hieu, nho hieu
va dung » van dung, va duong, vat dung

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu lang - thanh trung va dung phuong ((doan toan) or (dan toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - thanh trung va dung phuong ((doan toan) OR (dan toan)) cau.
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - thanh trung va dung phuong ((doan toan) or (dan toan)) cau*.