htdocs/assets/templates/searches/search/threatexchange/a.html
<div class="col-md-4 col-xs-12 form-group">
<label for="threatexchange_type">Search Type <span class="glyphicon glyphicon-question-sign" data-toggle="tooltip" title="The type of ThreatExchange query to perform."></span></label>
<select class="form-control" name="threatexchange_type">
<option value="malware">Malware</option>
<option value="threats">Threats</option>
</select>
</div>