Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh doi » thanh doi, hanh noi, hang doi
cam thuc » am thuc, nam thuc, can thuc
doi cua » dai cua, hoi cua
va hanh » van hanh, va thanh, va danh
cam thu » nam thu, cac thu, ca thu
su sach » so sach, vu sach
hieu ve » hieu va
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach y, sach 2
nang o » nang co, nang ho, nang ro
v nang » va nang, vu nang, van nang
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: su sach v nang o hoi. ((hieu ve) or (hieu van)) ((cam thuc) or (cam thu)) va hanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach v nang o hoi. ((hieu ve) OR (hieu van)) ((cam thuc) OR (cam thu)) va hanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach v nang o hoi. ((hieu ve) or (hieu van)) ((cam thuc) or (cam thu)) va hanh doi cua tre*.