Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
thong cong » trong cong, tong cong, thong thong
doc hieu » toc thieu, hoc thieu
tranh he » trinh he, tranh ha, tinh he
cong dan » cong san, cong tan, huong dan
toan cau » toan cao, toan tap, toan tai
toan ban » van 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) OR (hoc hien)) xanh - hanh tranh he thong cong dan ((toan cau) OR (toan ban))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) OR (hoc hien)) xanh - hanh tranh he thong cong dan ((toan cau) or (toan ban))~".
• Adding a wildcard symbol may retrieve word variants: ((doc hieu) OR (hoc hien)) xanh - hanh tranh he thong cong dan ((toan cau) or (toan ban))*.