Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
tang cua » hang cua, tang luan, thong cua
mang cua » manh cua, dung cua, ban cua
cong tac » cong ty
pham cau » phan cau, pham can, pha cau
ho hieu » ho chieu, hoi hieu, nho hieu
pham ca » pham can, pham ma, pham va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - hanh ((tang cua) OR (mang cua)) nhung cong tac ((pham cau) OR (pham ca))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - hanh ((tang cua) or (mang cua)) nhung cong tac ((pham cau) OR (pham ca))~".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - hanh ((tang cua) or (mang cua)) nhung cong tac ((pham cau) OR (pham ca))*.