Perhaps you should try some spelling variations:
thanh trung » thanh tung
thieu sach » chieu sach, thien hach, theo sach
hieu cach » hieu cac, chieu sach, hieu ca
dung cong » dung trong
trung ha » trung hoc, trung tam, trung cap
cong tac » cong ty
bang cau » hang cau, bang cac, nang cao
ha dung » hai dung, kha dung, nha dung
ran cau » van cau, ban cau, can cau

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: toc ((thieu sach) OR (hieu cach)) - thanh trung ha dung cong tac ((ran cau) OR (bang cau))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((thieu sach) OR (hieu cach)) - thanh trung ha dung cong tac ((ran cau) or (bang cau))~".
• Adding a wildcard symbol may retrieve word variants: toc ((thieu sach) OR (hieu cach)) - thanh trung ha dung cong tac ((ran cau) or (bang cau))*.