Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hien sach » dien sach, thien hach, chieu sach
kien sach » dien sach, vien bach, kien mac
trang va » hang va
tran van » luan van
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.

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien sach) OR (kien sach)) - banh ((trang va) OR (tran van)) nhung cong ban than cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien sach) or (kien sach)) - banh ((trang va) OR (tran van)) nhung cong ban than cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien sach) or (kien sach)) - banh ((trang va) OR (tran van)) nhung cong ban than cau*.