Perhaps you should try some spelling variations:
sach hanh » sach han, sac hanh, sach tranh
sach danh » sach tranh, sach dao, sach dung
xa nghiem » xet nghiem, van nghiem, va nghien
nghe moi » nghe noi, nghe nuoi, nghe hoa
hoc sach » hoc sinh, hoc cac, hoc anh
moi hoc » hoi hoc, mon hoc, mo hoc
sach xa » sach dao, sach nha, sach bai
d hoc » du hoc, de hoc, y hoc

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: (( vu ((sach hanh) OR (sach danh)) nghe moi hoc ) OR ( hoc sach xa nghiem ((d hoc) OR (ad hoc)) ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( vu ((sach hanh) OR (sach danh)) nghe moi hoc ) or ( hoc sach xa nghiem ((d hoc) or (ad hoc)) ))~".
• Adding a wildcard symbol may retrieve word variants: (( vu ((sach hanh) OR (sach danh)) nghe moi hoc ) or ( hoc sach xa nghiem ((d hoc) or (ad hoc)) ))*.