Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh vai » thanh hai, thanh van, thanh tai
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
cao duc » cao suc, giao duc, tao duoc
dao duc » giao duc, tao duoc
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
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 o hoi. hieu van ((cao duc) OR (dao duc)) van thanh vai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang o hoi. hieu van ((cao duc) OR (dao duc)) van thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang o hoi. hieu van ((cao duc) OR (dao duc)) van thanh vai cua tre*.