Perhaps you should try some spelling variations:
trien hoat » tien hoa
tinh dung » trinh dung, tinh quang, tinh huong
hieu soat » hieu suat, hieu hoat, hieu luat
van trien » van tien, va trien, van tren
dung tan » dung toan, duong tan, dung tai
van hieu » cao hieu
tan van » tran van, tang van, luan van

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

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