Perhaps you should try some spelling variations:
chieu xanh » chieu sang, chieu tinh, hieu manh
chieu sach » chinh sach, chiet tach, chieu sang
hanh trinh » canh tranh, hanh chinh
dung cong » dung trong
trinh su » trinh tu, trinh san, trinh cau
cong dan » cong san, cong tan, huong dan
van cau » van dau, van hau, van chat

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: theo ((chieu xanh) OR (chieu sach)) - hanh trinh su dung cong dan ((van cau) OR (phan tu))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu xanh) OR (chieu sach)) - hanh trinh su dung cong dan ((van cau) or (phan tu))~".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu xanh) OR (chieu sach)) - hanh trinh su dung cong dan ((van cau) or (phan tu))*.