Perhaps you should try some spelling variations:
hanh hai » thanh hai, nhanh hai, hang hai
thuc day » thuc dan, thuc vat
hieu van » hieu va, thien van, lieu va
truc va » thuc va, thuc vat, trung va
hai cua » thai cua, dai cua, hoi cua
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
van dau » van dao, phan dau
nang xa » lang xa, nang ma, mang xa
cua tre » cua te, cuu tre, cua triet

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 ((nang xa) OR (nang x)) hoi. hieu van dau ((truc va) OR (thuc day)) hanh hai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) OR (nang x)) hoi. hieu van dau ((truc va) or (thuc day)) hanh hai cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) OR (nang x)) hoi. hieu van dau ((truc va) or (thuc day)) hanh hai cua tre*.