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
tang cua » hang cua, tang luan, thong cua
mang cua » manh cua, dung cua, ban cua
cong tac » cong ty
tac tren » rac tren, tai tren, tap tren
tren cau » tren ca, tren cay, tren tau

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 - anh ((tang cua) or (mang cua)) dung cong tac tren cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu lang - anh ((tang cua) OR (mang cua)) dung cong tac tren cau.
• Adding a wildcard symbol may retrieve word variants: theo hieu lang - anh ((tang cua) or (mang cua)) dung cong tac tren cau*.