Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
danh va » doanh va, hanh va, anh va
va danh » va dinh, va dan, va hanh
cac toc » cac toi, cac nuoc, cac thoi
cac tuc » cac tu, cac tac, cac nuoc
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
va cua » va chua, via cua, ca cua

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 ((y nang) OR (v nang)) xa hoi. hieu van ((cac tuc) OR (cac toc)) va danh va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y nang) OR (v nang)) xa hoi. hieu van ((cac tuc) or (cac toc)) va danh va cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ((y nang) OR (v nang)) xa hoi. hieu van ((cac tuc) or (cac toc)) va danh va cua tre*.