Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
bang cac » nang cao, hang ca, dung cac
cac hoat » cao hoat, cac khoan, cac thuat
hanh tai » thanh tai, hang tai, han tai
tai cua » thai cua, tai cuc, tri cua
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, sach thu
ty bang » ty xang, te bang, ty hang
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
va cao » va cac, va co, va dao

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 ty bang cac hoat. hieu va cao ((xuc va) or (tuc va)) hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty bang cac hoat. hieu va cao ((xuc va) OR (tuc va)) hanh tai cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ty bang cac hoat. hieu va cao ((xuc va) or (tuc va)) hanh tai cua tre*.