Perhaps you should try some spelling variations:
cham hoc » cham soc, chat hoc, cham hoi
danh di » danh du, xanh di, danh dien
va danh » va dinh, va dan, va hanh
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach 2, sach vay
di cua » dai cua, doi cua, de cua
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach v) or (sach y)) nang ((x hoi) OR (o hoi)). hieu vu cham hoc va danh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach v) OR (sach y)) nang ((x hoi) OR (o hoi)). hieu vu cham hoc va danh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach v) or (sach y)) nang ((x hoi) OR (o hoi)). hieu vu cham hoc va danh di cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach v) or (sach y)) nang ((x hoi) OR (o hoi)). hieu vu cham hoc va danh di cua tre*.