Perhaps you should try some spelling variations:
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
so sach » bo sach, co sach, hoc sach
so sanh » do sanh
hieu ve » hieu va, hieu van
cau luc » cau truc, cau phuc
du cua » duy cua, dau cua, dum cua
ve cau » ke cau, va cau, ve cac
ang xa » lang xa, mang xa, dang xay
ty ang » ty xang, ty hang, ty anh
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) OR (so sanh)) ty ang xa hoi. hieu ve cau luc ((van hanh) or (ban hanh)) du cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) ty ang xa hoi. hieu ve cau luc ((van hanh) OR (ban hanh)) du cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (so sanh)) ty ang xa hoi. hieu ve cau luc ((van hanh) or (ban hanh)) du cua te".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (so sanh)) ty ang xa hoi. hieu ve cau luc ((van hanh) or (ban hanh)) du cua te*.