Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hang di » hang doi, hang vi, hang dien
hanh di » hanh vi, hanh de, danh di
cao luc » bao luc, cao duc, cao suc
cua tre » cua te, cuu tre, cua triet
vu nang » vuc nang, va nang, vu dang
luc va » duc va, tuc va, loc va
v nang » va nang, van nang, voi nang
va cao » va cac, va co, va dao
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: thu sach ((v nang) OR (vu nang)) o hoi. lieu va cao luc va ((hanh di) or (hang di)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((v nang) OR (vu nang)) o hoi. lieu va cao luc va ((hanh di) OR (hang di)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((v nang) OR (vu nang)) o hoi. lieu va cao luc va ((hanh di) or (hang di)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((v nang) OR (vu nang)) o hoi. lieu va cao luc va ((hanh di) or (hang di)) cua tre*.