Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh luan » trinh luat, trinh quan, trinh han
chong cong » thong cong, cuong cong, phong cong
hieu lang » chieu sang, hieu quang, nhieu tang
cong cong » cong dong, trong cong, dung cong
doi hieu » doi chieu, doc hieu, doi hien
toan cau » toan cao, toan ban, toan tai
toan tap » toan ban

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: doi hieu lang - hanh trinh luan ((chong cong) OR (cong cong)) van ((toan cau) OR (toan tap))~.
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - hanh trinh luan ((chong cong) or (cong cong)) van ((toan cau) or (toan tap))*.