Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
thanh va » thanh van, hanh va, thanh ha
sach ky » sac ky, sach y, sach ty
van cao » van dao, van bao, van hao
cao duc » dao duc, cao suc, giao duc
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua
x hoi » o hoi, x ho
5 hoi » o hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang ((((x hoi) or (5 hoi))) or (xa hoi)). hieu van cao duc van thanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ((((x hoi) OR (5 hoi))) OR (xa hoi)). hieu van cao duc van thanh va cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang ((((x hoi) or (5 hoi))) or (xa hoi)). hieu van cao duc van thanh va cua tre*.