Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
tang luan » dung luan
doi hieu » doi chieu, doc hieu, doi hien
tang cua » mang cua, hang cua, thong cua
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cau » toan cau, phan cau, than cap

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 - hanh ((tang cua) or (tang luan)) nhung cong dan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - hanh ((tang cua) OR (tang luan)) nhung cong dan than cau.
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - hanh ((tang cua) or (tang luan)) nhung cong dan than cau*.