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
su sach » so sach, vu sach
doi cua » dai cua, hoi cua
va hanh » van hanh, va thanh, va danh
cam thu » nam thu, cac thu, ca thu
sach vu » sach va, sach tu, sach uu
hieu ve » hieu va
vu nang » vuc nang, va nang, vu dang
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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 vu nang x 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 vu nang x 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 vu nang x hoi. ((hieu ve) or (hieu van)) ((cam thuc) or (cam thu)) va hanh doi cua tre*.