Perhaps you should try some spelling variations:
doanh giai » doanh giao, doanh ngoai, doanh tai
sach thu » sach thue, sach thieu, sach tham
lang van » hoang van, giang van, hang va
tang van » hoang van, trong van, tang luan
dang van » hoang van, hang va
ta doanh » va doanh, te doanh, ty doanh
giai cua » gian cua, gia cua, giai ca
te sach » toc sach
cac toc » cac toi, cac nuoc, cac thoi
toc ta » toc tay, toc thai
cua te » cua tu

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 thu ((((lang van) OR (tang van))) OR (dang van)) hoi. lieu va cac toc ta doanh giai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach thu ((((lang van) OR (tang van))) or (dang van)) hoi. lieu va cac toc ta doanh giai cua te~".
• Adding a wildcard symbol may retrieve word variants: te sach thu ((((lang van) OR (tang van))) or (dang van)) hoi. lieu va cac toc ta doanh giai cua te*.