Perhaps you should try some spelling variations:
hoc thuc » hoc huu
hang tai » hang va
thuc ban » thuoc ban, thuc dan, thu ban
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
van hoc » van hoa
ty nang » ky nang, ty hang, ly nang
cua tre » cua te, cuu tre, cua triet

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 ((ty nang) OR (ty xang)) xa hoi. hieu van hoc thuc ban ((hang tai) OR (dung tai)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ty nang) OR (ty xang)) xa hoi. hieu van hoc thuc ban ((hang tai) or (dung tai)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ((ty nang) OR (ty xang)) xa hoi. hieu van hoc thuc ban ((hang tai) or (dung tai)) cua tre*.