Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
tranh cua » doanh cua, manh cua
tang cua » mang cua, hang cua, tang luan
cong tac » cong ty
toan cao » toan ban, toan tap
ho hieu » ho chieu, hoi hieu, nho hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu lang - hanh ((tranh cua) or (tang cua)) nhung cong tac ((toan cao) or (van ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - hanh ((tranh cua) OR (tang cua)) nhung cong tac ((toan cao) OR (van ban)).
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - hanh ((tranh cua) or (tang cua)) nhung cong tac ((toan cao) or (van ban))*.