Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
van nang » van quang, van ban, van dong
lieu van » lieu va, hieu van, sieu van
van tuan » van quan, van ban, anh tuan
vu nang » vuc nang, va nang, vu dang
hang di » hang doi, hang vi, hang dien
cua tre » cua te, cuu tre, cua triet
luc va » tuc va, loc va
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ((vu nang) or (van nang)) xa hoi. lieu van tuan ((luc va) or (duc va)) hang di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((vu nang) OR (van nang)) xa hoi. lieu van tuan ((luc va) OR (duc va)) hang di cua tre.
• Adding a wildcard symbol may retrieve word variants: hoc sach ((vu nang) or (van nang)) xa hoi. lieu van tuan ((luc va) or (duc va)) hang di cua tre*.