Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
dieu cua » dieu tra
te sach » toc sach
van cau » van dau, van hau, van chat
cau hoc » cau hoi, cau hoa, cao hoc
va danh » va dinh, va dan, va hanh
v nang » va nang, vu nang, van nang
de cua » le cua, te cua

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: te sach ((v nang) OR (cam nang)) xa hoi. hieu van cau hoc va danh ((de cua) OR (dieu cua)) triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((v nang) or (cam nang)) xa hoi. hieu van cau hoc va danh ((de cua) OR (dieu cua)) triet~".
• Adding a wildcard symbol may retrieve word variants: te sach ((v nang) or (cam nang)) xa hoi. hieu van cau hoc va danh ((de cua) OR (dieu cua)) triet*.