Perhaps you should try some spelling variations:
lang thang » cang thang, dang thanh, hung thang
hieu lang » chieu sang, hieu quang, nhieu tang
bang cong » dang cong, bang song, hang cong
dung cong » dung trong
thang ban » hang ban, tang ban, thanh ban
doi hieu » doi chieu, doc hieu, doi hien
cong dai » cong dan, cong hai, cong da

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 - thanh cong dai ((bang cong) or (dung cong)) lang thang ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - thanh cong dai ((bang cong) OR (dung cong)) lang thang ban*.