Perhaps you should try some spelling variations:
sach van » sach han, sach va, bach van
van nang » van quang, van ban, van dong
ban hanh » ban hang
thuc ban » thuoc ban, thuc dan, thu ban
so sach » so sanh, bo sach, co sach
nang xa » nang x, lang xa, nang ma
ve cau » ke cau, ve cac, le cau
de cua » le cua, dieu cua
te cua » tue cua, le cua
va cau » van cau, va cac, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach van nang xa hoi. hieu ((ve cau) OR (va cau)) thuc ban hanh ((de cua) or (te cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach van nang xa hoi. hieu ((ve cau) OR (va cau)) thuc ban hanh ((de cua) OR (te cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach van nang xa hoi. hieu ((ve cau) OR (va cau)) thuc ban hanh ((de cua) or (te cua)) tre".
• Adding a wildcard symbol may retrieve word variants: so sach van nang xa hoi. hieu ((ve cau) OR (va cau)) thuc ban hanh ((de cua) or (te cua)) tre*.