Show playlist youtube in a rectangle

I used this code in rectangle but It only displayed 19 videos,not displayed all youtube list by search.
How can I set result by search about 50 videos?

<script type="text/javascript">

function go_get(){
 var base_url = 'http://www.youtube.com/embed?listType=search&amp&list=';
 var search_field = document.getElementById('yourtextfield').value;
 var target_url = base_url + search_field;
 var ifr = document.getElementById('youriframe');
 ifr.src = target_url;
 return false;
}

</script> 
<iframe id="youriframe" width="100%" height="100%"></iframe>

I don’t see any way to change this based on their iFrame Player API Documentation, so I’m guessing the answer is no. If YouTube has developer forums you might want to ask there since it is more of a question for them.

(Though their REST API does have a way to set maxResults, but it appears this parameter is ignored if I try to add it to your base_url).