Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu va » lieu va
cam luc » cam xuc, cau luc
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
luc va » duc va, tuc va, loc va
de cua » le cua, te cua, dieu cua
x hoi » xa hoi, o hoi, x ho

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 v nang x hoi. ((hieu va) or (hieu qua)) cam luc va van de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach v nang x hoi. ((hieu va) OR (hieu qua)) cam luc va van de cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach v nang x hoi. ((hieu va) or (hieu qua)) cam luc va van de cua tre*.