Perhaps you should try some spelling variations:
doan tinh » doan hinh, ban tinh, quan tinh
hieu suat » hieu luat, hieu qua
tinh soat » tinh toan, tinh chat, sinh hoat
luat dan » luat dat, luat doanh, cua dan
dan doan » dan toan, tan doan, van doan
tin ung » tin dung, tinh dung, trinh ung
ung nam » sung nam, uong nam, dung nam
va hieu » van hieu, va dieu, va hien

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 va hieu suat ) or ( trinh luat dan doan tinh soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin ung nam va hieu suat ) OR ( trinh luat dan doan tinh soat ))*.