Perhaps you should try some spelling variations:
sach tay » xach tay, sach hay, sach nay
tay lang » tai lang, tay tang, tay quang
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
hoc van » hoc dan, hoc va, hoc vat
cao hoc » co hoc, cho hoc, chat hoc
hieu ke » hieu kem, chieu ke, hieu ky
ke cao » ke cau, ke co, te cao
ha hoi » hoa hoi, ha noi, va hoi
di cua » doi cua, de cua, do 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: te sach tay lang ((ha hoi) OR (xa hoi)). hieu ke cao hoc van hanh ((di cua) OR (dai cua)) te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tay lang ((ha hoi) OR (xa hoi)). hieu ke cao hoc van hanh ((di cua) or (dai cua)) te~".
• Adding a wildcard symbol may retrieve word variants: te sach tay lang ((ha hoi) OR (xa hoi)). hieu ke cao hoc van hanh ((di cua) or (dai cua)) te*.