Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
nang xa » nang x, lang xa, nang ma
lang ha » long ha
qua cac » cua cac
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
xuc va » tuc va, luc va, xac va
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y ((nang xa) or (lang ha)) hoi. hieu qua cac ((xuc va) or (duc va)) hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((nang xa) OR (lang ha)) hoi. hieu qua cac ((xuc va) OR (duc va)) hanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach y ((nang xa) or (lang ha)) hoi. hieu qua cac ((xuc va) or (duc va)) hanh di cua tre*.