Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hieu vien » hieu viec, thieu nien, hieu tieng
hai cua » thai cua, dai cua, hoi cua
va danh » va dinh, va dan, va hanh
cac xuc » cam xuc, cac nuoc, chat xuc
vu sach » vu bach, su sach, vu khach
lang xa » lang ha, dang xay, lang van
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
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: vu sach ky lang xa hoi. ((hieu vien) OR (hieu hien)) cac xuc ((va danh) or (gia thanh)) hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky lang xa hoi. ((hieu vien) OR (hieu hien)) cac xuc ((va danh) OR (gia thanh)) hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky lang xa hoi. ((hieu vien) OR (hieu hien)) cac xuc ((va danh) or (gia thanh)) hai cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ky lang xa hoi. ((hieu vien) OR (hieu hien)) cac xuc ((va danh) or (gia thanh)) hai cua tre*.