Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
thanh tung » thanh cong
va trong » va truong, va tuong, va trung
va thong » va thuong, va phuong, he thong
cong san » cong tac
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 ((thieu sach) OR (thien hach)) - thanh tung ((va trong) or (va thong)) cong san toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - thanh tung ((va trong) OR (va thong)) cong san toan cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) OR (thien hach)) - thanh tung ((va trong) or (va thong)) cong san toan cao*".