Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
phai la » phai lam, phan lap, phan lan
cua tre » cua te, cuu tre, cua triet
phi la » phi va, phu la, phi ha
vi cua » vai cua, di cua
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 ky nang x hoi. ((hieu van) OR (hieu va)) chau ((phi la) OR (phai la)) hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang x hoi. ((hieu van) or (hieu va)) chau ((phi la) OR (phai la)) hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. ((hieu van) or (hieu va)) chau ((phi la) OR (phai la)) hanh vi cua tre*.