Perhaps you should try some spelling variations:
quang tran » quang tuan, quang trung, quang thanh
dung quan » dung quang, dung luan, luong quan
hieu suat » hieu luat, hieu qua
quang tan » quang tuan, quang toan, quang ban
kiem soat » kiem toan
van kiem » va kiem, van kien, van hieu
quan li » quan ly, quan tri
li hieu » ly hieu, le hieu, li hien

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