Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh mai » hanh ma, hanh mau, hanh may
va triet » va thiet, va trien, cua triet
ve triet » va trien, su triet
ky lang » ky nang, ky dang, ky tang
lang ha » long ha
hoc van » hoc dan, hoc va, hoc vat
su xac » pu xac, su cac
xac ky » cac ky, sac ky, bac ky
ha hoi » hoa hoi, ha noi, xa hoi
qua ca » qua cac, qua cua, qua cai
ca hoc » cao hoc, cua hoc, cac hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: su xac ky lang ha hoi. hieu qua ca hoc van hanh mai ((va triet) or (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su xac ky lang ha hoi. hieu qua ca hoc van hanh mai ((va triet) OR (ve triet)).
• Adding a wildcard symbol may retrieve word variants: su xac ky lang ha hoi. hieu qua ca hoc van hanh mai ((va triet) or (ve triet))*.