Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
hai cua » thai cua, dai cua, hoi cua
anh hai » lanh hai, manh hai, anh thai
cuu ban » cuu van, cua ban, cuu san
cuc ban » cua ban, cac ban, duc ban
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
hieu ve » hieu van
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang

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 ky tang xa hoi. ((hieu ve) or (hieu va)) cam ((cuc ban) OR (cuu ban)) anh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky tang xa hoi. ((hieu ve) OR (hieu va)) cam ((cuc ban) OR (cuu ban)) anh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky tang xa hoi. ((hieu ve) or (hieu va)) cam ((cuc ban) OR (cuu ban)) anh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky tang xa hoi. ((hieu ve) or (hieu va)) cam ((cuc ban) OR (cuu ban)) anh hai cua tre*.