Perhaps you should try some spelling variations:
thanh tranh » thanh thanh, thanh tran, thanh trang
tranh luan » trinh luan, trinh luat, doanh luan
luan chong » luan chung, luan cong, luan phong
hieu sang » chieu sang, hieu lang, hieu quang
cong lang » cong vang, cong luong, cong quang
doc hieu » toc thieu, hoc thieu, hoc hien
cong san » cong tac
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu sang - thanh tranh luan chong ((cong san) or (cong lang)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sang - thanh tranh luan chong ((cong san) OR (cong lang)) toan cao.
• Adding a wildcard symbol may retrieve word variants: doc hieu sang - thanh tranh luan chong ((cong san) or (cong lang)) toan cao*.