Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
hanh di » hanh vi, hanh de, hang di
su viet » so viet
van cau » van dau, van hau, van chat
y nang » ky nang, ly nang, v nang
luc va » duc va, tuc va, loc va
xac va » tac va, ac va, bac va
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: tu sach y nang x hoi. hieu van cau ((xac va) OR (luc va)) hanh di ((cua triet) OR (su viet))~.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang x hoi. hieu van cau ((xac va) or (luc va)) hanh di ((cua triet) or (su viet))*.