Perhaps you should try some spelling variations:
thien van » thi van
su sach » so sach, vu sach
cac toc » cac toi, cac nuoc, cac thoi
so sanh » do sanh
vu nang » vuc nang, va nang, vu dang
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
vi cua » vai cua, di cua
toc va » hoc va, toc ta, tuc va
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

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: ((su sach) OR (so sanh)) vu nang x hoi. ((hieu va) OR (thien van)) cac toc va hanh vi cua te~.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sanh)) vu nang x hoi. ((hieu va) or (thien van)) cac toc va hanh vi cua te*.