Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
tranh manh » tran manh, tranh minh, tran minh
hieu lang » chieu sang, hieu quang, nhieu tang
manh hung » anh huong
doi hieu » doi chieu, doc hieu, doi hien
cong tac » cong ty
phan cau » phan dau, phan cac, phan lap

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 - canh tranh manh hung ((cong tac) or (cong thanh)) ((phan cau) or (phan tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - canh tranh manh hung ((cong tac) OR (cong thanh)) ((phan cau) OR (phan tu)).
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - canh tranh manh hung ((cong tac) or (cong thanh)) ((phan cau) or (phan tu))*.