Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
van dau » van dao, phan dau
cua tre » cua te, cuu tre, cua triet
y dang » ky dang, 2 dang, _ dang
xac va » tac va, ac va, bac va
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((y dang) or (ky nang)) xa hoi. hieu van dau ((xac va) or (tuc va)) thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((y dang) OR (ky nang)) xa hoi. hieu van dau ((xac va) OR (tuc va)) thanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ((y dang) or (ky nang)) xa hoi. hieu van dau ((xac va) or (tuc va)) thanh vi cua tre*.