Perhaps you should try some spelling variations:
tinh huong » dinh huong, anh huong
huong luan » huong lan, cuong luan, huong loan
kiem soat » kiem toan
quang cua » quan cua, quang tuan, quang huy
hieu soat » hieu suat, hieu hoat, hieu so
hieu luat » hieu qua
van kiem » va kiem, van kien, van hieu
cua cao » cua cac, cu cao, cua cay

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