Perhaps you should try some spelling variations:
bach tuoc » sach duoc, sach nuoc
van bach » van bac, van hach, van sach
va doanh » van doanh, vay doanh, va danh
hieu van » hieu va, thien van, lieu va
tuoc va » thuoc va, nuoc va, duoc va
te sach » toc sach
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
o hoi » co hoi, o hoc, o hai

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 v nang ((5 hoi) OR (o hoi)). hieu van bach tuoc va doanh ((vi lua) OR (vi luu)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach v nang ((5 hoi) or (o hoi)). hieu van bach tuoc va doanh ((vi lua) OR (vi luu)) tre~".
• Adding a wildcard symbol may retrieve word variants: te sach v nang ((5 hoi) or (o hoi)). hieu van bach tuoc va doanh ((vi lua) OR (vi luu)) tre*.