Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
nhung cong » dung cong, thong cong, hang cong
hieu quan » hieu qua, lieu quan, thien quan
hieu lang » chieu sang, hieu quang, nhieu tang
trinh cua » tinh cua, trinh luat, trinh quan
cua nhung » va nhung
tan toan » tan tran, van toan, dan toan
tap toan » tap doan, tap quan, bai toan

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hai ((hieu quan) OR (hieu lang)) - hanh trinh cua nhung cong ((tan toan) OR (tap toan)) cau~.
• Adding a wildcard symbol may retrieve word variants: hai ((hieu quan) or (hieu lang)) - hanh trinh cua nhung cong ((tan toan) or (tap toan)) cau*.