Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
hieu ve » hieu va
cao duc » dao duc, cao suc, giao duc
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
vi cuu » vinh cuu
vi luu » vi lua
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 y nang x hoi. ((hieu ve) OR (hieu van)) cao duc va hanh ((vi cuu) OR (vi luu)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang x hoi. ((hieu ve) OR (hieu van)) cao duc va hanh ((vi cuu) or (vi luu)) tre~".
• Adding a wildcard symbol may retrieve word variants: su sach y nang x hoi. ((hieu ve) OR (hieu van)) cao duc va hanh ((vi cuu) or (vi luu)) tre*.