Perhaps you should try some spelling variations:
chiet tach » chieu sach
thanh tung » thanh cong
nhung dong » nhung don, nhung cong, nhung dung
hieu cach » hieu cac, chieu sach, hieu ca
cua nhung » va nhung
dong bang » dong san
bang than » bang thanh, ban than, sang than
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu cach) or (chiet tach)) - ((thanh trung) OR (thanh tung)) cua nhung dong bang than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu cach) OR (chiet tach)) - ((thanh trung) OR (thanh tung)) cua nhung dong bang than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu cach) or (chiet tach)) - ((thanh trung) OR (thanh tung)) cua nhung dong bang than cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu cach) or (chiet tach)) - ((thanh trung) OR (thanh tung)) cua nhung dong bang than cau*.