Perhaps you should try some spelling variations:
thanh tuong » thanh thuong, thanh tung, thanh huong
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
tuong cua » truong cua, huong cua, thong cua
bang cong » dang cong, bang song, hang cong
ban toan » bai toan, ban than, bao toan
van toan » van tuan, van tan, van thanh
ho hieu » ho chieu, hoi hieu, nho hieu

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 tuong cua ((nhung cong) or (bang cong)) ((ban toan) OR (van toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - thanh tuong cua ((nhung cong) OR (bang cong)) ((ban toan) OR (van toan)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - thanh tuong cua ((nhung cong) or (bang cong)) ((ban toan) OR (van toan)) cau".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - thanh tuong cua ((nhung cong) or (bang cong)) ((ban toan) OR (van toan)) cau*.