Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
tranh cua » doanh cua
dung cong » dung trong
manh cua » doanh cua, ban cua
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than tap » toan tap, han tap, phan 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)) - canh ((tranh cua) OR (manh cua)) dung cong dan than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - canh ((tranh cua) OR (manh cua)) dung cong dan than tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) or (thien hach)) - canh ((tranh cua) OR (manh cua)) dung cong dan than tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (thien hach)) - canh ((tranh cua) OR (manh cua)) dung cong dan than tap*.