TerSia

in the form class :

    for track in Track.objects.all():
        trackList.append((track.id,track.name))  
    track = forms.CharField(label=_('track'), required=False, widget=forms.SelectMultiple(choices=trackList))


in the search method:

            chosenTracks = []
            for trackId in form.clean_data['track']:
                print trackId
#                 chosenTracks.extend(Track.objects.get(pk=trackId))