Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
cua triet » cua viet
cac thuc » cach thuc, cac thu, can thuc
thanh di » thanh doi, thanh de, thanh do
va triet » va thiet, va trien, ve triet
su triet » su viet, su tien, ve triet
co sach » bo sach, cuon sach, hoc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua

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

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ky nang xa hoi. hieu va cac thuc vat thanh di ((((cua triet) OR (va triet))) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ky nang xa hoi. hieu va cac thuc vat thanh di ((((cua triet) OR (va triet))) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach ky nang xa hoi. hieu va cac thuc vat thanh di ((((cua triet) OR (va triet))) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: co sach ky nang xa hoi. hieu va cac thuc vat thanh di ((((cua triet) OR (va triet))) or (su triet))*.