Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
thanh tung » thanh cong
nhung cong » dung cong, thong cong, hang cong
hoc thieu » toc thieu, hoc hien
cua nhung » va nhung
ban toan » bai toan, van toan, bao toan
ban than » ban thanh, van thanh, ban hang

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 - ((thanh trung) or (thanh tung)) cua nhung cong ((ban toan) OR (ban than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - ((thanh trung) OR (thanh tung)) cua nhung cong ((ban toan) OR (ban than)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu sach - ((thanh trung) or (thanh tung)) cua nhung cong ((ban toan) OR (ban than)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - ((thanh trung) or (thanh tung)) cua nhung cong ((ban toan) OR (ban than)) cau*.