Perhaps you should try some spelling variations:
cang thang » cong thanh, dang thanh
nhung cong » dung cong, thong cong, nhung don
hieu lang » chieu sang, hieu quang, nhieu tang
hang cong » dang cong, hang nong, bang cong
doi hieu » doi chieu, doc hieu, doi hien
thang va » hang va, trang va, thong va
van phan » van phong, van thanh, luan phan
phan dau » phan tu, hang dau

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 - cang thang va ((nhung cong) or (hang cong)) van phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - cang thang va ((nhung cong) OR (hang cong)) van phan dau.
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - cang thang va ((nhung cong) or (hang cong)) van phan dau*.