Perhaps you should try some spelling variations:
thanh tuong » thanh thuong, thanh tung, thanh huong
hieu xanh » chieu xanh, hieu manh, hieu nganh
doc hieu » toc thieu, hoc thieu, hoc hien
tuong va » truong va, thuong va, luong va
cong dan » huong dan, cong dong, cong tac
cong san » cong tac
cong tan » cong tac, cong thanh, cong ty
toan cau » toan cao, toan ban, toan tap

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: doc hieu xanh - thanh tuong va nhung ((((cong dan) OR (cong san))) OR (cong tan)) toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - thanh tuong va nhung ((((cong dan) OR (cong san))) or (cong tan)) toan cau~".
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - thanh tuong va nhung ((((cong dan) OR (cong san))) or (cong tan)) toan cau*.