Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hanh trang » thanh trung, canh tranh, hanh trinh
trang luan » tang luan, tranh luan, trang tuan
hieu manh » chieu xanh, hieu nganh, dieu hanh
dang toan » dang tran, dung toan, dang thanh
van cong » van dong, van phong, phan cong
dan toan » van toan, dan than, manh toan

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

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