Perhaps you should try some spelling variations:
hanh trang » thanh trung, canh tranh, hanh trinh
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
doi hieu » doi chieu, doc hieu, doi hien
trang va » tran van, hang va
cong tan » cong tac, cong san, cong thanh
toan cau » toan ban, toan tap, toan tai
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: doi hieu lang - hanh trang va nhung cong tan ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - hanh trang va nhung cong tan ((toan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - hanh trang va nhung cong tan ((toan cau) or (toan cao))*.