Perhaps you should try some spelling variations:
chong cong » cong cong, thong cong, cuong cong
hieu sach » chieu sach, hieu cach, hieu cac
dien sach » dien anh
tranh cua » doanh cua, manh cua
cua chong » cua cong, cua chung, cua khong
dan chinh » dang chinh, van chinh, ban chinh
lan chinh » luan chinh, van chinh, hanh chinh

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) or (dien sach)) - canh tranh cua chong cong ((dan chinh) OR (lan chinh)) can~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu sach) OR (dien sach)) - canh tranh cua chong cong ((dan chinh) OR (lan chinh)) can.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu sach) or (dien sach)) - canh tranh cua chong cong ((dan chinh) OR (lan chinh)) can".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu sach) or (dien sach)) - canh tranh cua chong cong ((dan chinh) OR (lan chinh)) can*.