Perhaps you should try some spelling variations:
thanh tung » thanh cong
luan phung » luan phuong, luan chung, luan phong
bien tinh » bi tinh, yen tinh, diep tinh
cong dan » cong san, cong tan, huong dan
cong tac » cong ty
than tap » toan tap, han tap, phan tap
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 (thanh tung)) luan phung ((cong dan) or (cong tac)) than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so bien tinh - ((thanh trung) OR (thanh tung)) luan phung ((cong dan) OR (cong tac)) than tap*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so bien tinh - ((thanh trung) OR (thanh tung)) luan phung ((cong dan) or (cong tac)) than tap*".