Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
than duc » tran duc, phan duc, than doc
duc ban » duc tan, duc van, dua ban
tu sach » thu sach, su sach, te sach
va than » va thanh, van than, va phan
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
o hoi » co hoi, o hoc, o hai
vi va » vai va, vu va, bi va

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 ((y nang) OR (v nang)) o hoi. lieu va than duc ban thanh ((vi va) OR (vi van)) triet~.
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) or (v nang)) o hoi. lieu va than duc ban thanh ((vi va) or (vi van)) triet*.