Perhaps you should try some spelling variations:
cua triet » su triet, va triet
van thanh » ban thanh, van tuan
hoc sach » hoc sinh, hoc cac, hoc anh
thanh va » thanh van, hanh va, thanh ha
cua viet » ca viet, hoa viet, cua vat
duc van » duc va, duc tan, duc manh
va cao » va cac, va co, va bao
y nang » ky nang, ly nang, v nang
va dao » ca dao
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: hoc sach y nang x hoi. hieu ((va cao) OR (va dao)) duc van thanh va ((cua triet) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach y nang x hoi. hieu ((va cao) OR (va dao)) duc van thanh va ((cua triet) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach y nang x hoi. hieu ((va cao) OR (va dao)) duc van thanh va ((cua triet) or (cua viet))".
• Adding a wildcard symbol may retrieve word variants: hoc sach y nang x hoi. hieu ((va cao) OR (va dao)) duc van thanh va ((cua triet) or (cua viet))*.