Perhaps you should try some spelling variations:
chien tranh » hien trang
dung luat » dung luan, dung quat, dung cua
hieu soat » hieu suat, hieu hoat, hieu luat
quang tan » quang tuan, quang tran, quang toan
hien hanh » dieu hanh
dat hieu » dao hieu, dat tieu, rat nhieu
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 luat dat hieu soat ) or ( tinh quang tan van ((chien tranh) or (hien hanh)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung luat dat hieu soat ) OR ( tinh quang tan van ((chien tranh) OR (hien hanh)) )).
• Adding a wildcard symbol may retrieve word variants: (( tin dung luat dat hieu soat ) or ( tinh quang tan van ((chien tranh) or (hien hanh)) ))*.