Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » thien van, lieu va, hieu ve
hanh vai » hanh vi, hanh va, hanh tai
hieu va » lieu va, hieu qua
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

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 (o hoi)). ((hieu van) or (hieu va)) cau truc va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang ((x hoi) OR (o hoi)). ((hieu van) OR (hieu va)) cau truc va hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach y nang ((x hoi) or (o hoi)). ((hieu van) or (hieu va)) cau truc va hanh vai cua tre*.