Perhaps you should try some spelling variations:
lang thang » cang thang, dang thanh, hung thang
quan trong » gian trong
hieu lang » chieu sang, hieu quang, nhieu tang
cong doan » cong dan, cong hoan, dong doanh
doan phan » doanh phan, toan phan, dan phan
doi hieu » doi chieu, doc hieu, doi hien
lang van » dang van, tang van, hoang van

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 - ((lang van) or (lang thang)) quan trong cong doan phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - ((lang van) OR (lang thang)) quan trong cong doan phan tu*.