Perhaps you should try some spelling variations:
quang toan » quang tuan, quang tran, quang doan
lang quang » dang quang, hang quang, long quang
tinh dung » trinh dung, tin dung, tinh quang
hieu soat » hieu suat, hieu hoat, hieu luat
dinh lang » dinh long, dinh rang, dinh quang
tien soat » trien hoat, thien hoat, kiem soat
van hieu » cao hieu
luan » quan, 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 dung luan van hieu soat ) or ( dinh lang quang toan tien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh dung luan van hieu soat ) OR ( dinh lang quang toan tien soat )).
• Adding a wildcard symbol may retrieve word variants: (( tinh dung luan van hieu soat ) or ( dinh lang quang toan tien soat ))*.