Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhieu tang » chieu sang, hieu lang, nhiet nang
hanh trang » thanh trung, canh tranh, hanh trinh
dang cong » dung cong
trang va » tran van, hang va
cong tan » cong tac, cong san, cong thanh
than cau » phan cau, than cap, thanh chau
toan cau » toan cao, toan ban, toan tap
va dang » van dang, va nang, va lang

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: ho ((chieu sach) OR (nhieu tang)) - hanh trang va dang cong tan ((than cau) OR (toan cau))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sach) or (nhieu tang)) - hanh trang va dang cong tan ((than cau) OR (toan cau))~".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) or (nhieu tang)) - hanh trang va dang cong tan ((than cau) OR (toan cau))*.