Perhaps you should try some spelling variations:
hien sach » dien sach, thien hach, chieu sach
kien sach » dien sach, vien bach, kien mac
hang cong » dang cong, hang nong, bang cong
tranh va » tranh van, trang va, trinh va
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cau » toan cau, phan cau, than cap
va hang » van hang, 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: hoc ((hien sach) OR (kien sach)) - canh tranh va hang cong dan than cau~.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien sach) or (kien sach)) - canh tranh va hang cong dan than cau*.