Perhaps you should try some spelling variations:
quang luan » quan luan, quang tuan, quang uan
tinh dung » tin dung, tinh huong, anh dung
hieu suat » hieu luat, hieu qua
kiem soat » kiem toan
quan van » luan van, quan va, quan luan
van hieu » cao hieu
luan va » luan van, luat va
va kiem » van kien

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: (( ((tinh dung) OR (trinh dung)) quan van hieu suat ) OR ( tinh quang luan va kiem soat ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((tinh dung) OR (trinh dung)) quan van hieu suat ) or ( tinh quang luan va kiem soat ))~".
• Adding a wildcard symbol may retrieve word variants: (( ((tinh dung) OR (trinh dung)) quan van hieu suat ) or ( tinh quang luan va kiem soat ))*.