Perhaps you should try some spelling variations:
vu khach » vu khanh, vu khac, vay khach
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
thanh di » thanh doi, thanh de, thanh do
cau tren » cu tren, dau tren, ca tren
so sach » so sanh, bo sach, co sach
van cao » van dao, van bao, van hao
cao duc » dao duc, cao suc, giao duc
di cau » da cau, diem cau
x hoi » xa hoi, o hoi, x ho

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 (vu khach)) ky nang x hoi. hieu van cao duc va thanh di cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (vu khach)) ky nang x hoi. hieu van cao duc va thanh di cau tren.
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (vu khach)) ky nang x hoi. hieu van cao duc va thanh di cau tren*.