Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
va cao » va cac, va co, va dao
vi cua » vai cua, di cua
va cam » va cham, va cac, va cai

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

• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y ((nang xa) OR (nang ma)) hoi. lieu ((va cam) OR (va cao)) truc va hanh vi cua tre~.
• Adding a wildcard symbol may retrieve word variants: toc sach y ((nang xa) or (nang ma)) hoi. lieu ((va cam) or (va cao)) truc va hanh vi cua tre*.