Perhaps you should try some spelling variations:
chiet tach » chieu sach
nhung cong » dung cong, thong cong, hang cong
dang vat » dang van, dong vat, dang nhat
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap
dang va » dang van, hang va, dung va

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 ((ho manh) OR (chiet tach)) - anh ((dang va) OR (dang vat)) nhung cong dan than cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((ho manh) or (chiet tach)) - anh ((dang va) OR (dang vat)) nhung cong dan than cao~".
• Adding a wildcard symbol may retrieve word variants: theo ((ho manh) or (chiet tach)) - anh ((dang va) OR (dang vat)) nhung cong dan than cao*.