Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
toc sach » hoc sach, doc sach, thuoc sach
sach thi » sach thu, sach tai, sach thieu
ban hanh » ban hang
cham xuc » cam xuc, chat xuc, cham soc
van cham » van chat, van tham, va cham
hieu van » hieu va, thien van, lieu va
thi nang » thi cong, ki nang, thi hanh
hai cua » thai cua, dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
o hai » co hai, so hai, o lai
o hoi » co hoi, o hoc, o hoa

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 thi nang ((o hoi) OR (o hai)). hieu van cham xuc ((van thanh) or (ban hanh)) hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thi nang ((o hoi) OR (o hai)). hieu van cham xuc ((van thanh) OR (ban hanh)) hai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach thi nang ((o hoi) OR (o hai)). hieu van cham xuc ((van thanh) or (ban hanh)) hai cua tre*".