Perhaps you should try some spelling variations:
khau sach » hau sach, khoa sach, pham sach
hanh tang » hanh trang, anh tang, hanh mang
tang luan » dung luan
luan nang » luan van, van nang, luan san
nang cong » nang song, dang cong, bang cong
rau sach » cau sach, hau sach, nam sach
cong dan » cong san, cong tan, huong dan
toan cau » toan cao, toan ban, toan tai
toan tap » toan ban

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

• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((rau sach) OR (khau sach)) - hanh tang luan nang cong dan ((toan cau) OR (toan tap))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((rau sach) or (khau sach)) - hanh tang luan nang cong dan ((toan cau) OR (toan tap))~".
• Adding a wildcard symbol may retrieve word variants: theo ((rau sach) or (khau sach)) - hanh tang luan nang cong dan ((toan cau) OR (toan tap))*.