Perhaps you should try some spelling variations:
diep quang » dinh quang
hanh tran » hanh trang, thanh tran, hanh tram
lang cong » dang cong, bang cong, hang cong
tran van » luan van
van lang » van nang, va lang, van hang
cong san » cong tac
san than » sang than, san thanh, ban 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: ho ((diep quang) or (hieu qua)) - hanh tran van lang cong san than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((diep quang) OR (hieu qua)) - hanh tran van lang cong san than cau.
• Adding a wildcard symbol may retrieve word variants: ho ((diep quang) or (hieu qua)) - hanh tran van lang cong san than cau*.