Perhaps you should try some spelling variations:
tieng trung » truong trung
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
hanh dung » thanh dung, anh dung, hanh dong
hoi hieu » hoi phieu, hoi tieu, moi hieu
dan toan » van toan, dan than, manh toan
toan cau » 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: hoi hieu lang - hanh dung luan ((nhung cong) or (tieng trung)) dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu lang - hanh dung luan ((nhung cong) OR (tieng trung)) dan toan cau.
• Adding a wildcard symbol may retrieve word variants: hoi hieu lang - hanh dung luan ((nhung cong) or (tieng trung)) dan toan cau*.