Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, ma hoa
y nang » ky nang, ly nang, v nang
tuc va » thuc va, truc va, tuc xa
vi cuu » vi luu, vinh cuu

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 ma hoi. ((hieu ve) OR (hieu van)) cam ((duc va) OR (tuc va)) hanh vi cuu tre~.
• Adding a wildcard symbol may retrieve word variants: toc sach y nang ma hoi. ((hieu ve) or (hieu van)) cam ((duc va) or (tuc va)) hanh vi cuu tre*.