Perhaps you should try some spelling variations:
chieu sach » chinh sach, chieu sang, chieu xanh
canh trinh » canh tranh, hanh trinh, canh tinh
cong van » cong vang, cong san, song van
van phan » van phong, van thanh, luan phan
phan cau » phan dau, phan cac, phan tu
vi hang » voi hang, va hang, si hang
vi hanh » vi thanh, va hanh, ve hanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((chieu sach) or (chiet tach)) - canh trinh ((vi hang) OR (vi hanh)) cong van phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sach) OR (chiet tach)) - canh trinh ((vi hang) OR (vi hanh)) cong van phan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sach) or (chiet tach)) - canh trinh ((vi hang) OR (vi hanh)) cong van phan cau".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) or (chiet tach)) - canh trinh ((vi hang) OR (vi hanh)) cong van phan cau*.