Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
hanh de » hanh ve, hanh kem
hang de » hoang de, hang di, hang ke
xuc ban » duc ban, cuc ban, quoc ban
nam xuc » cam xuc, nam xua, nam thuc
cua tre » cua te, cuu tre, cua triet

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 ((tu nano) or (truc nano)) xa hoi. hieu van nam xuc ban ((hang de) OR (hanh de)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((tu nano) OR (truc nano)) xa hoi. hieu van nam xuc ban ((hang de) OR (hanh de)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((tu nano) or (truc nano)) xa hoi. hieu van nam xuc ban ((hang de) OR (hanh de)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((tu nano) or (truc nano)) xa hoi. hieu van nam xuc ban ((hang de) OR (hanh de)) cua tre*.