Perhaps you should try some spelling variations:
hien xanh » hien hanh, hien nhanh, chieu xanh
hanh tran » hanh trang, thanh tran, hanh tram
van nhung » van nhuong, va nhung, van hung
tran van » luan van
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien xanh - hanh tran van nhung ((cong dan) or (cong san)) than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh tran van nhung ((cong dan) OR (cong san)) than cau*.