Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
van cac » van hac, van cau, van bac
cuu tre » cua tre, cau tren, cau treo
o hoi » co hoi, o hoc, o hoa
o hai » co hai, so hai, o lai
d cuu » _ cuu

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: su sach ky nang ((o hoi) OR (o hai)). hieu van cac ((cua ban) OR (cuu van)) anh d cuu tre~.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((o hoi) or (o hai)). hieu van cac ((cua ban) or (cuu van)) anh d cuu tre*.