Perhaps you should try some spelling variations:
hieu sach » chieu sach, hieu cach, dien sach
dvan dung » dan dung, doan duong, van dong
doc hieu » toc thieu, hoc thieu, hoc hien
van dung » van dong, xay dung, tin dung
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu sach - thanh cong ((dvan dung) or (van dung)) cong san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sach - thanh cong ((dvan dung) OR (van dung)) cong san toan cau.
• Adding a wildcard symbol may retrieve word variants: doc hieu sach - thanh cong ((dvan dung) or (van dung)) cong san toan cau*.