Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh tai » thanh tai, hang tai, han tai
tang van » dang van, hoang van, trong van
cam tuc » cam xuc, cam tu, nam thuc
van tai » von tai, van tuan
hieu va » lieu va, hieu qua
van hoi » van hoa, van hoc, van hoe
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ky tang van hoi. hieu va cam tuc xa ((hanh tai) or (van tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky tang van hoi. hieu va cam tuc xa ((hanh tai) OR (van tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ky tang van hoi. hieu va cam tuc xa ((hanh tai) or (van tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ky tang van hoi. hieu va cam tuc xa ((hanh tai) or (van tai)) cua tre*.