Perhaps you should try some spelling variations:
thanh trung » thanh tung
tieu sach » chieu sach, dien sach, te sach
hanh tang » hanh trang, anh tang, hanh mang
dong cong » duong cong, dung cong, dang cong
cua dong » chua dong, cua cong, cua dang
cong tan » cong tac, cong san, cong thanh
tan van » tran van, tang van, luan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo tieu sach - ((hanh tang) or (thanh trung)) cua dong cong tan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo tieu sach - ((hanh tang) OR (thanh trung)) cua dong cong tan van ban.
• Adding a wildcard symbol may retrieve word variants: theo tieu sach - ((hanh tang) or (thanh trung)) cua dong cong tan van ban*.