Perhaps you should try some spelling variations:
hieu suat » hieu luat, hieu qua
van hieu » cao hieu
luat dan » luat dat, luat doanh, cua dan
dan doan » dan toan, tan doan, van doan
doan tin » doan tinh, toan tin, doan thien
tin soat » tin so, tin bat, tin phat
tin ung » tin dung, tinh dung, trinh ung
ung nam » sung nam, uong nam, dung nam
nam van » nam dan, nam va, pham 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 ung nam van hieu suat ) or ( trinh luat dan doan tin soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin ung nam van hieu suat ) OR ( trinh luat dan doan tin soat ))*.