Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
va cham » va chat, va tham
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
doc va » duoc va, hoc va, duc va
loc va » hoc va, luc va
di cua » dai cua, doi cua, de cua
x hoi » o hoi, x ho, 5 hoi

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

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