Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
van cac » van hac, van cau, van bac
cac xuc » cam xuc, cac nuoc, chat xuc
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ho, nang ro
xuc va » duc va, tuc va, luc va
vi cua » vai cua, di cua
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: ((su sach) or (toc sach)) ky nang o hoi. hieu van cac xuc va thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (toc sach)) ky nang o hoi. hieu van cac xuc va thanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (toc sach)) ky nang o hoi. hieu van cac xuc va thanh vi cua tre*.