Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
ban thanh » ban hanh, ban hang
thu sach » tu sach, thuat sach, thuoc sach
van cua » vang cua, ban cua, dan cua
tuc ban » thuc ban, truc ban, tu ban
cua tre » cua te, cuu tre, cua triet
ty lang » tay lang, ty hang, tu lang
va cai » va bai, va dai, va cao

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 ((ty lang) OR (ty xang)) xa hoi. hieu ((va cai) or (va cac)) tuc ban thanh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ty lang) OR (ty xang)) xa hoi. hieu ((va cai) OR (va cac)) tuc ban thanh van cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ty lang) OR (ty xang)) xa hoi. hieu ((va cai) or (va cac)) tuc ban thanh van cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ty lang) OR (ty xang)) xa hoi. hieu ((va cai) or (va cac)) tuc ban thanh van cua tre*.