Perhaps you should try some spelling variations:
thanh trung » thanh tung
sang sach » ban sach, sang tac, dung sach
trong san » trong cac, cong san, dong san
cua dung » cua dang, cua dong, cua rung
qua dung » quang dung, su dung, qua song
san toan » van toan, dan toan, manh toan
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((sang sach) or (mang sach)) - thanh trung ((cua dung) or (qua dung)) trong san toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((sang sach) OR (mang sach)) - thanh trung ((cua dung) OR (qua dung)) trong san toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc ((sang sach) or (mang sach)) - thanh trung ((cua dung) or (qua dung)) trong san toan cao*.