Perhaps you should try some spelling variations:
doanh doanh » toan doanh, doanh hoan, doanh thanh
hieu sang » chieu sang, hieu lang, hieu quang
doc hieu » toc thieu, hoc thieu, hoc hien
doanh va » doan va, doanh tai, doanh cua
cong dan » cong san, huong dan, cong dong
cong tan » cong tac, cong san, cong thanh
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: doc hieu sang - doanh doanh va nhung ((cong dan) OR (cong tan)) ((toan cau) OR (toan tap))~.
• Adding a wildcard symbol may retrieve word variants: doc hieu sang - doanh doanh va nhung ((cong dan) or (cong tan)) ((toan cau) or (toan tap))*.