Perhaps you should try some spelling variations:
hieu sach » chieu sach, hieu cach, dien sach
chung cua » chung cu, dung cua, huong cua
hang cong » dang cong, hang nong, bang cong
doc hieu » toc thieu, hoc thieu, hoc hien
hung cua » huong cua, khung cua, dung cua
cong dan » cong san, cong tan, huong dan
dan van » dang van, doan van, dao van

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu sach - manh ((hung cua) or (chung cua)) hang cong dan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sach - manh ((hung cua) OR (chung cua)) hang cong dan van ban.
• Adding a wildcard symbol may retrieve word variants: doc hieu sach - manh ((hung cua) or (chung cua)) hang cong dan van ban*.