Perhaps you should try some spelling variations:
dung lsan » dung luan, dung san, dung nhan
hieu suat » hieu luat, hieu qua
quang uan » quang tuan, quang ban, quang tran
kiem soat » kiem toan
lsan van » luan van, san van, lan van
van hieu » cao hieu
va kiem » van kien
uan va » luan va, quan va, ban va

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

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