He does try here:
What is a democratic socialist? Bernie Sanders tries to redefine the name.
“What democratic socialism means to me,” Sanders said during a recent speech in New Hampshire, “is having a government which represents all people, rather than just the wealthiest people, which is most often the case right now in this country.”
Somebody needs to ask Bernie what the hell this has to do with
socialism in the first place because it would appear that he doesn't understand what socialism really is (common ownership of the means of production and production for use), he is just changing the definition of the word to suit his political needs, the definition he outlines here is so broad and excludes the economic specifics of what is generally understood as socialism that it is essentially meaningless.