Perhaps you should try some spelling variations:
su sach » so sach, vu sach
cao hoi » cau hoi, co hoi, cao hoc
hanh va » hang va, hanh vi
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
va bao » va bai
bao va » bao ve, tao va, ban va
va cua » va chua, via cua, ca cua
so va » so van, so vat, su va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang cao hoi. lieu va bao ((so va) or (bao va)) hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang cao hoi. lieu va bao ((so va) OR (bao va)) hanh va cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach y nang cao hoi. lieu va bao ((so va) or (bao va)) hanh va cua tre*.