update activity admin

biz/admin.py

@@ -435,10 +435,10 @@ class ProspectGroupAdmin(SyncedObjectAdmin):
 
 @admin.register(Activity)
 class ActivityAdmin(SyncedObjectAdmin):
+    raw_id_fields = ['prospects']
     list_display = ('prospect_names', 'last_update', 'status', 'type', 'description', 'attachment_text', )
     list_filter = ('status', 'type')
-    search_fields = ('description',)
-    filter_horizontal = ('prospects',)
+    search_fields = ('attachment_text',)
     date_hierarchy = 'last_update'
 
     def get_form(self, request, obj=None, **kwargs):