Perhaps you should try some spelling variations:
nhanh hai » nhanh thai, thanh hai, nhanh ha
ban nhanh » ban hanh, ban thanh, ban nhan
quoc ban » quoc bao, quoc lan, quoc quan
cau quoc » cac quoc, cao quoc, han quoc
hieu van » hieu va, thien van, lieu va
hai cua » thai cua, dai cua, hoi cua
van cau » van dau, van hau, van chat
cua tre » cua te, cuu tre, cua triet
sach ky » sach y, sach ty, sach kem
lang ha » long ha
lang xa » dang xay, lang van
sac ky » cac ky, sai ky

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) ((lang xa) OR (lang ha)) hoi. hieu van cau quoc ban nhanh hai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) ((lang xa) OR (lang ha)) hoi. hieu van cau quoc ban nhanh hai cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) ((lang xa) OR (lang ha)) hoi. hieu van cau quoc ban nhanh hai cua tre*.