Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, theo sach
hieu cach » hieu cac, chieu sach, hieu ca
canh manh » lanh manh, canh tranh, cach mang
dung cong » dung trong
manh cua » doanh cua, ban cua
van bang » van ban, van nang, von bang
bang cau » hang cau, bang cac, nang cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((thieu sach) OR (hieu cach)) - canh manh cua ((dang cong) or (dung cong)) van bang cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((thieu sach) OR (hieu cach)) - canh manh cua ((dang cong) OR (dung cong)) van bang cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((thieu sach) OR (hieu cach)) - canh manh cua ((dang cong) or (dung cong)) van bang cau".
• Adding a wildcard symbol may retrieve word variants: toc ((thieu sach) OR (hieu cach)) - canh manh cua ((dang cong) or (dung cong)) van bang cau*.