Perhaps you should try some spelling variations:
ban doanh » van doanh, san doanh, toan doanh
ban danh » ban hanh, ban dan, van danh
hieu van » hieu va, thien van, lieu va
so sach » so sanh, bo sach, co sach
bao thu » bao thuc, ba thu, ban thu
van bao » van ban, van dao
nang ma » tang ma, sang ma, nang cao
vi cua » vai cua, di cua
cua te » cua tu

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 y ((nang x) or (nang ma)) hoi. hieu van bao thu ((ban danh) OR (ban doanh)) vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((nang x) OR (nang ma)) hoi. hieu van bao thu ((ban danh) OR (ban doanh)) vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y ((nang x) or (nang ma)) hoi. hieu van bao thu ((ban danh) OR (ban doanh)) vi cua te".
• Adding a wildcard symbol may retrieve word variants: so sach y ((nang x) or (nang ma)) hoi. hieu van bao thu ((ban danh) OR (ban doanh)) vi cua te*.