Styjun

I'm trying to create a search capability in my Django project that will filter multiple models (currently 3). It works for a single model and an additional model tied by a foreign key. But, when I added a dropdown menu for the third model not containing a direct reference to the initial model, I got an error saying they keyword was unavailable (because it wasn't looking in the model):

Cannot resolve keyword 'rooms' into field. Choices are: DateBegin, FAN, IS, Location, PI, holdings, id

Models:

#models.py
class rooms(models.Model):
 ContainerLocation = models.CharField(max_length=100, blank=True, null=True)
 Database = models.CharField(max_length=100, blank=True, null=True)
 Name = models.CharField(max_length=100, blank=True, null=True)
 Datatype = models.CharField(max_length=100, blank=True, null=True)

class holdings(models.Model):
 Contents = models.CharField(max_length=700, blank=True, null=True, default='No description')
 FAN = models.ForeignKey('surveys', on_delete=models.SET_NULL, blank=True, null=True)
 Database = models.ForeignKey('rooms', on_delete=models.SET_NULL, blank=True, null=True)
 ...(more fields)...

class surveys(models.Model): 
 FAN = models.SlugField(max_length=100, blank=True, null=True)
 PI = models.CharField(max_length=100, blank=True, null=True)
 IS = models.CharField(max_length=100, blank=True, null=True)
 DateBegin = models.DateField(blank=True, null=True)
 Location = models.CharField(max_length=200, blank=True, null=True) 

Filter:

#filters.py
from django import forms
from datalibrary.models import surveys, rooms, holdings
import django_filters

class MultiFilter(django_filters.FilterSet):
 FAN = django_filters.CharFilter(lookup_expr='icontains', distinct=True)
 PI = django_filters.CharFilter(lookup_expr='icontains', distinct=True)
 Location = django_filters.CharFilter(lookup_expr='icontains', distinct=True)
 Contents = django_filters.CharFilter(field_name='holdings__Contents', lookup_expr='icontains', label='Contents', distinct=True)
 Room = django_filters.ModelChoiceFilter(queryset=rooms.objects.all(), label='Room', distinct=True)

class Meta:
 model = surveys
 fields = ['FAN', 'PI', 'Location', 'Contents', 'Room']

Views:

#views.py
def search(request):
 multifilter = MultiFilter(request.GET, queryset=surveys.objects.all())
 return render(request, 'search_results.html', 'filter': multifilter)

Is it possible to build a filter with django-filters that searches multiple models? Can I create a merged queryset or something like that? I tried adding a list to the filters Meta (e.g. model = [surveys, rooms, holdings]) but that obviously doesn't work.

If django-filters can't do it, are there other options for searching multiple models in Django?