Perhaps you should try some spelling variations:
huong luan » huong lan, cuong luan, huong loan
hieu suat » hieu luat, hieu qua
quang tan » quang tuan, quang tran, quang toan
kiem soat » kiem toan
van kiem » va kiem, van kien, van hieu
luan va » luan van, luat va
va hieu » van hieu, va dieu, va hien
tan van » tran van, tang van, luan van

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( anh huong luan va hieu suat ) or ( tinh quang tan van kiem soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( anh huong luan va hieu suat ) OR ( tinh quang tan van kiem soat )).
• Adding a wildcard symbol may retrieve word variants: (( anh huong luan va hieu suat ) or ( tinh quang tan van kiem soat ))*.