Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh li » thanh loi, thanh le, nhanh li
so sach » so sanh, bo sach, co sach
cao duc » dao duc, cao suc, tao duoc
ca tren » cau tren, cu tren, la tren
hieu ve » hieu va, hieu van
vu sach » vu bach, su sach, vu khach
x hoi » xa hoi, o hoi, x ho
li ca » ly ca

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 sach)) ky nang x hoi. hieu ve ((cao duc) OR (giao duc)) ban thanh li ca tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (vu sach)) ky nang x hoi. hieu ve ((cao duc) OR (giao duc)) ban thanh li ca tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (vu sach)) ky nang x hoi. hieu ve ((cao duc) OR (giao duc)) ban thanh li ca tren".
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (vu sach)) ky nang x hoi. hieu ve ((cao duc) OR (giao duc)) ban thanh li ca tren*.