Perhaps you should try some spelling variations:
manh hai » lanh hai, minh hai, thanh hai
quoc ban » quoc bao, quoc lan, quoc quan
tu sach » thu sach, su sach, te sach
xuc ban » duc ban, cuc ban, xuat ban
hai cua » thai cua, dai cua, hoi cua
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
hieu ve » hieu van
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
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: tu sach ky dang xa hoi. ((hieu ve) or (hieu va)) cam ((xuc ban) OR (quoc ban)) manh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang xa hoi. ((hieu ve) OR (hieu va)) cam ((xuc ban) OR (quoc ban)) manh hai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky dang xa hoi. ((hieu ve) or (hieu va)) cam ((xuc ban) OR (quoc ban)) manh hai cua tre*".