Perhaps you should try some spelling variations:
quang quan » quang tuan, quang uan, quan quan
thien hoat » trien hoat, thien thuat, tien hoa
hieu soat » hieu suat, hieu hoat, hieu luat
dinh dung » dinh duong, dinh hung, tinh dung
kiem soat » kiem toan
quan van » quan va, quan luan, quan doan
van hieu » cao hieu
tinh » trinh, minh, kinh
luan » lan

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

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