Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
cau tren » cu tren, dau tren, ca tren
thanh di » thanh doi, thanh de, thanh do
vu khach » vu khanh, vu khac, vay khach
hieu ve » hieu va, hieu van
cao duc » dao duc, cao suc, giao duc
duc ban » duc tan, duc van, dua ban
su sach » so sach, vu sach
ve cao » va cao, ve bao, ve cac
di cau » da cau, diem cau
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (vu khach)) ky nang ((x hoi) or (xa hoi)). hieu ve cao duc ban thanh di cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu khach)) ky nang ((x hoi) OR (xa hoi)). hieu ve cao duc ban thanh di cau tren.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu khach)) ky nang ((x hoi) or (xa hoi)). hieu ve cao duc ban thanh di cau tren*.