Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
thuc van » thuc vat, thuc dan, thuc hanh
te sach » toc sach
qua cam » qua cham, qua cac, qua ca
thuc va » thuc vat, thuc dan, thuc day
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ho, nang ro
di cua » dai cua, doi cua, de cua
o hoi » co hoi, o hoc, o hai

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 thu nang o hoi. hieu qua cam ((thuc van) OR (thuc va)) hanh di cua tre~.
• Adding a wildcard symbol may retrieve word variants: te sach thu nang o hoi. hieu qua cam ((thuc van) or (thuc va)) hanh di cua tre*.