Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
xuc van » luc van, vuc van, xuc ban
duc van » duc va, duc tan, duc manh
cua duc » cua tuc, cua nuoc, cua quoc
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
ma hoi » mai hoi, xa hoi, ma hoa
cua tu » cua tuc, cua su, cua cu

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 v nang ma hoi. hieu va cac ((xuc van) OR (duc van)) hanh vi ((cua duc) OR (cua tu))~.
• Adding a wildcard symbol may retrieve word variants: toc sach v nang ma hoi. hieu va cac ((xuc van) or (duc van)) hanh vi ((cua duc) or (cua tu))*.