Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dan dien » doan dien, danh dien, dan den
dien cu » dien cuc, dien cua, dien tu
hieu su » hieu sau, tieu su, hieu so
su cham » su pham, tu cham, vu cham
nang xa » nang x, lang xa, nang ma
2 nang » v nang
soc va » hoc va, doc va, goc va
loc va » hoc va, luc va
cu tre » cu tren, cua tre, cuu tre

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: ((te sach) OR (toc sach)) 2 nang xa hoi. hieu su cham ((soc va) OR (loc va)) dan dien cu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) 2 nang xa hoi. hieu su cham ((soc va) or (loc va)) dan dien cu tre~".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) 2 nang xa hoi. hieu su cham ((soc va) or (loc va)) dan dien cu tre*.