Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
ve triet » va trien
su triet » su viet, su tien
sach ky » sac ky, sach y, sach ty
van cau » van dau, van hau, van chat
luc va » tuc va, loc 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: thu sach ky nang x hoi. hieu van cau ((duc va) OR (luc va)) hanh vi ((ve triet) OR (su triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang x hoi. hieu van cau ((duc va) or (luc va)) hanh vi ((ve triet) OR (su triet))~".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang x hoi. hieu van cau ((duc va) or (luc va)) hanh vi ((ve triet) OR (su triet))*.