Perhaps you should try some spelling variations:
dung quan » dung quang, dung luan, luong quan
hieu suat » hieu luat, hieu qua
tinh quan » tinh quang, trinh quan, tin quan
thanh van » thanh san, thanh toan, thanh phan
kiem soat » kiem toan
quan vo » quan vi, quan va, quan ve
vo hieu » co hieu, va hieu, cao hieu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung quan vo hieu suat ) OR ( tinh quan ((thanh van) OR (tinh toan)) kiem soat ))~.
• Adding a wildcard symbol may retrieve word variants: (( tin dung quan vo hieu suat ) or ( tinh quan ((thanh van) or (tinh toan)) kiem soat ))*.