Perhaps you should try some spelling variations:
tinh dung » trinh dung, tin dung, tinh huong
dung qsan » dung quan, dung san, dung quang
hieu soat » hieu suat, hieu hoat, hieu luat
quang san » quang ban, quang uan, quang van
kien soat » bien soan, kien hoa, dien hoat
kiem soat » kiem toan
qsan van » quan van, quang van, luan van
van hieu » cao hieu
san van » tan van, luan van, tran van

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

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