Perhaps you should try some spelling variations:
thanh trung » thanh tung
dang phung » dang hung, bang phuong, dung phuong
bien tinh » bi tinh, yen tinh, diep tinh
cua dang » cua cong, cua ban
van toan » van tuan, van tan, van thanh
toan tap » toan ban
so bien » mot bien

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

• Performing a fuzzy search may retrieve terms with similar spellings: so bien tinh - ((thanh trung) or (canh tranh)) cua dang phung van toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so bien tinh - ((thanh trung) OR (canh tranh)) cua dang phung van toan tap*.