Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
tu sach » thu sach, su sach, te sach
xuc ban » duc ban, quoc ban, xuat ban
hai cua » thai cua, dai cua, hoi cua
anh hai » lanh hai, manh hai, anh thai
cuc ban » cua ban, cac ban, cuu ban
cua tre » cua te, cuu tre, cua triet
hang xa » hoang xa, hang va, hang ca
ty hang » ly hang, ty xang, thi hang
qua ca » qua cac, qua cua, qua cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (thuoc sach)) ty hang xa hoi. hieu qua ca ((xuc ban) OR (cuc ban)) anh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ty hang xa hoi. hieu qua ca ((xuc ban) OR (cuc ban)) anh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thuoc sach)) ty hang xa hoi. hieu qua ca ((xuc ban) OR (cuc ban)) anh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ty hang xa hoi. hieu qua ca ((xuc ban) OR (cuc ban)) anh hai cua tre*.