Perhaps you should try some spelling variations:
hanh trang » thanh trung, canh tranh, hanh trinh
luan trong » quan trong, luat trong, luan tuong
hanh tang » anh tang, hanh mang, hanh tung
theo dau » theo mau, thau dau, te dau
dau sach » cau sach, dat sach, hau sach
cong tap » cuong tap, cong tac, cong tan
doan cau » doan dau, doan cap, doanh chau
toan cau » toan cao, toan ban, toan tap

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

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