Perhaps you should try some spelling variations:
theo hieu » theo chieu, theo tieu, thien hieu
hieu lang » chieu sang, hieu quang, nhieu tang
dung cong » dung trong
cong dan » cong san, cong tan, huong dan
thanh ca » thanh cha, thanh cac, thanh ha
toan cao » toan ban, toan tap
am dung » am duong, lam dung, ap dung

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo hieu lang - ((thanh tung) or (thanh cong)) am dung cong dan ((thanh ca) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu lang - ((thanh tung) OR (thanh cong)) am dung cong dan ((thanh ca) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: theo hieu lang - ((thanh tung) or (thanh cong)) am dung cong dan ((thanh ca) or (toan cao))*.