Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hieu lang » chieu sang, hieu quang, nhieu tang
trinh cua » tinh cua, trinh luat, trinh quan
cua nhung » va nhung
doc hieu » toc thieu, hoc thieu, hoc hien
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
chan cau » phan cau, can cau, chinh cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu lang - hanh trinh cua nhung ((cong dan) or (cong san)) chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu lang - hanh trinh cua nhung ((cong dan) OR (cong san)) chan cau.
• Adding a wildcard symbol may retrieve word variants: doc hieu lang - hanh trinh cua nhung ((cong dan) or (cong san)) chan cau*.