Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
nhung cong » dung cong, thong cong, hang cong
hoc thieu » toc thieu, hoc hien
tranh cua » manh cua
doanh cua » doanh luan
van toan » van tuan, van tan, van thanh
dan than » dan chan, ban than, van than

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