Perhaps you should try some spelling variations:
bieu hien » dieu khien, bien phien, bien nien
dieu hien » dieu khien, dieu kien, dien bien
tinh va » tich va, trinh van, trinh vat
cac lao » cac loai, cac giao, cac lang
sach ty » sach y, sach tu, sach thu
tu sach » thu sach, su sach, te sach
ty lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet
ca lao » cua lao, ca dao, ca cao
va cua » va chua, via cua, ca cua

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 ty lang xa hoi. ((dieu hien) OR (bieu hien)) ((cac lao) OR (ca lao)) may tinh va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty lang xa hoi. ((dieu hien) OR (bieu hien)) ((cac lao) or (ca lao)) may tinh va cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach ty lang xa hoi. ((dieu hien) OR (bieu hien)) ((cac lao) or (ca lao)) may tinh va cua tre*.