Perhaps you should try some spelling variations:
tieu sach » chieu sach, dien sach, te sach
hanh tang » hanh trang, anh tang, hanh mang
tang dan » tang van, tung dan, tang luan
dan dung » van dung, tin dung, ap dung
cong dan » cong san, cong tan, cong dong
toan cao » toan ban
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: theo tieu sach - hanh tang dan dung ((cong dan) or (huong dan)) ((toan cao) OR (toan tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo tieu sach - hanh tang dan dung ((cong dan) OR (huong dan)) ((toan cao) OR (toan tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo tieu sach - hanh tang dan dung ((cong dan) or (huong dan)) ((toan cao) OR (toan tap))".
• Adding a wildcard symbol may retrieve word variants: theo tieu sach - hanh tang dan dung ((cong dan) or (huong dan)) ((toan cao) OR (toan tap))*.