Perhaps you should try some spelling variations:
chieu sach » chinh sach, chieu sang, chieu xanh
trinh hoan » trinh han, trinh toan, trinh chuan
nhung cong » dung cong, thong cong, hang cong
trinh hoa » trinh do, trinh han
cong ban » cong bang, cong san, cong tan
ban than » ban thanh, van thanh, ban hang
than cau » toan cau, phan cau, than cap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chieu sach) OR (chiet tach)) - hanh ((trinh hoan) or (trinh hoa)) nhung cong ban than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sach) OR (chiet tach)) - hanh ((trinh hoan) OR (trinh hoa)) nhung cong ban than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sach) OR (chiet tach)) - hanh ((trinh hoan) or (trinh hoa)) nhung cong ban than cau".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sach) OR (chiet tach)) - hanh ((trinh hoan) or (trinh hoa)) nhung cong ban than cau*.