Perhaps you should try some spelling variations:
sach hoi » sach doi, sach moi, cach thoi
hoi nang » hoi lang, ho nang, hoa nang
hanh hoi » hanh thoi, hanh noi, hanh hoa
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
qua cac » cua cac
soc van » hoc van, sac van, soc dan
hoi cua » hoi chuc
cua tre » cua te, cuu tre, cua triet
oc van » hoc van, luoc van, quoc van

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: tu sach hoi nang xa hoi. hieu qua cac ((soc van) OR (oc van)) hanh hoi cua tre~.
• Adding a wildcard symbol may retrieve word variants: tu sach hoi nang xa hoi. hieu qua cac ((soc van) or (oc van)) hanh hoi cua tre*.