keep in mind, main stream media are effectively perpetrating a black out of bernie's rallies, marches, etc. - so you may think bernie "should do more" because this is exactly what the hillary campaign wants you and the african american community to believe.
bernie was the first to proactively respond and engage in talks with black lives matter. within 3 days after the very first black lives matters interruption at a talk he was giving - he met with them and presented plans addressing their issues. bernie listened and continues listening -
bernie has addressed how to put money back into infrastructure to create jobs, free college tuition, $15 and hour - living wage for all people - including african americans and latinos, et al.
all of bernie's platform addresses issues in communities of color across the country. these are issues critical in the african american community as well as other communities. bernie does not define the issues nor his platform and plans as solely for any one specific ethnic or cultural group.
bernie addressed the privatization of prisons and the institutionalized racism resulting in the proportionately higher arrests of blacks and other people of color -long before hillary - and he did so without defining it as solely an issue for the african american community.
there is, however, one group bernie has not addressed specifically - the native american - indigenous - first nations people of america.