Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
phan thuc » nhan thuc, phap thuc, pham thuc
hoc sach » hoc sinh, hoc cac, hoc anh
tang van » dang van, hoang van, trong van
thuc ban » thuoc ban, thuc dan, thu ban
van hoi » van hoa, van hoc, van hoe
hieu ve » hieu va, hieu van
ve phan » va phan, ke phan, ve phat
vai cua » dai cua, hai cua, lai cua
sach o » sach lo, sac o, sach y
o tang » do tang, 6 tang, 7 tang
vi cua » di cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach o tang van hoi. hieu ve phan thuc ban thanh ((vi cua) or (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach o tang van hoi. hieu ve phan thuc ban thanh ((vi cua) OR (vai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: hoc sach o tang van hoi. hieu ve phan thuc ban thanh ((vi cua) or (vai cua)) tre*.