Perhaps you should try some spelling variations:
hieu lang » chieu sang, hieu quang, nhieu tang
chinh tai » chinh tri
chinh sua » chinh su, chinh cua, chinh luan
nhu hieu » nhu hien, nha hieu, nho hieu
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
toan cau » toan cao, toan ban, toan tap

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

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