filter by contact field email in podio restful API
<p>I'm trying to filter entries in my podio app by the email field (using the restful API URLs) that is located in the contact field. When I pull back the data I see that the email is deeply nested in the contact field object like this:</p>

<pre><code>{
      "type": "contact",
      "field_id": 80911192,
      "label": "Personal Information",
      "values": [
        {
          "value": {
            "user_id": null,
            "space_id": 2873853,
            "type": "space",
            "image": null,
            "profile_id": 176014555,
            "org_id": null,
            "phone": [
              "4045559996"
            ],
            "link": "google.com",
            "mail": [
              "somedudesemail@crap.com"
            ],
            "external_id": null,
            "last_seen_on": null,
            "name": "some dude"
          }
        }
      ],
      "config": {
        "settings": {
          "type": "space_contacts",
          "valid_types": [
            "space"
          ]
        },
        "mapping": null,
        "label": "Personal Information"
      },
      "external_id": "personal-information"
    },
</code></pre>

<p>how do you filter/search via the URL API by deeply nested sub-fields?
is it possible or is that a glaring limitation of podio?</p>