Perhaps you should try some spelling variations:
thanh dung » thanh duong, thanh hung, hanh dung
thanh tung » thanh cong
hieu lang » chieu sang, hieu quang, nhieu tang
luan cong » luat cong, luong cong, luan chung
cong cong » cong dong, trong cong, dung cong
doi hieu » doi chieu, doc hieu, doi hien
cong dan » cong san, cong tan, huong dan
toan cau » toan cao, toan tap, toan tai
toan ban » van ban

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