Perhaps you should try some spelling variations:
dung phuong » dung thuong, bang phuong, dung chung
phuong dan » phuong danh, phuong doan, huong dan
hieu lang » chieu sang, hieu quang, nhieu tang
doi hieu » doi chieu, doc hieu, doi hien
tranh su » trinh su, trang su, tranh cua
than cau » toan cau, phan cau, than cap
hang dau » hang va, hang tai

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 su dung phuong dan ((than cau) or (hang dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - canh tranh su dung phuong dan ((than cau) OR (hang dau)).
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - canh tranh su dung phuong dan ((than cau) or (hang dau))*.