Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hanh trinh » canh tranh, hanh chinh
hanh tinh » nhanh tinh, thanh tinh, canh tinh
tuong dan » huong dan, tung dan, truong dai
xuong dan » huong dan, xuong san, nguong dan
ho chieu » theo chieu, hoc thieu, doi chieu
toan tap » toan ban

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 - ((hanh tinh) OR (hanh trinh)) va nhung ((tuong dan) or (xuong dan)) toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho chieu sach - ((hanh tinh) OR (hanh trinh)) va nhung ((tuong dan) OR (xuong dan)) toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chieu sach - ((hanh tinh) OR (hanh trinh)) va nhung ((tuong dan) or (xuong dan)) toan tap".
• Adding a wildcard symbol may retrieve word variants: ho chieu sach - ((hanh tinh) OR (hanh trinh)) va nhung ((tuong dan) or (xuong dan)) toan tap*.