Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hang hai » hoang hai, hang tai, thanh hai
hanh hai » thanh hai, nhanh hai, hanh tai
hieu van » hieu va, thien van, lieu va
van tham » van thanh, van tuan, van chat
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach y, sach 2
loc va » hoc va
luc va » duc va, tuc va
nang o » nang co, nang ho, nang ro
v nang » va nang, vu nang, van nang
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 o hoi. hieu van tham ((luc va) or (loc va)) ((hanh hai) OR (hang hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach v nang o hoi. hieu van tham ((luc va) OR (loc va)) ((hanh hai) OR (hang hai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach v nang o hoi. hieu van tham ((luc va) or (loc va)) ((hanh hai) OR (hang hai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach v nang o hoi. hieu van tham ((luc va) or (loc va)) ((hanh hai) OR (hang hai)) cua tre*.