Perhaps you should try some spelling variations:
hoc sach » hoc cac, hoc anh
hanh tai » thanh tai, hang tai, han tai
cua tre » cua te, cuu tre, cua triet
ky lang » ky nang, ky dang, ky tang
lang ha » long ha
tai cua » thai cua, tai cuc, tri cua
va hanh » van hanh, va thanh, va danh
xuc va » duc va, tuc va, luc va
va dao » ca dao
ha hoi » hoa hoi, ha noi, xa hoi
va cao » va cac, va co, va bao

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: ((hoc sinh) OR (hoc sach)) ky lang ha hoi. hieu ((va cao) OR (va dao)) xuc va hanh tai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc sinh) or (hoc sach)) ky lang ha hoi. hieu ((va cao) OR (va dao)) xuc va hanh tai cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((hoc sinh) or (hoc sach)) ky lang ha hoi. hieu ((va cao) OR (va dao)) xuc va hanh tai cua tre*.