Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hieu manh » chieu xanh, hieu nganh, dieu hanh
hanh mang » nhanh mang, hanh trang, nhanh lang
hang cong » dang cong, hang nong, bang cong
cong san » cong tac
toan cao » toan ban
toan tap » toan ban
mang va » mang vua, hang va, bang va
va hang » van hang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((hieu manh) or (chieu sach)) - hanh mang va hang cong san ((toan cao) OR (toan tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu manh) OR (chieu sach)) - hanh mang va hang cong san ((toan cao) OR (toan tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu manh) or (chieu sach)) - hanh mang va hang cong san ((toan cao) OR (toan tap))".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu manh) or (chieu sach)) - hanh mang va hang cong san ((toan cao) OR (toan tap))*.