Template Search Button

I am trying to modify my search button in opencart. Everything looks ok except when I hit enter (submit the search word). It gives me an error...
I am not good at coding...I hope you can help me to fix it. Thank you for your time!

Here is the new search.tpl code:
<div id="search" class="input-group">
<form action="<?php echo $search; ?>" class="search-form">
<div class="form-group has-feedback">
<input type="text" name="search" value="<?php echo $search; ?>" placeholder="<?php echo $text_search; ?>" id="search" class="form-control input-lg" />
<span class="glyphicon glyphicon-search form-control-feedback input-group-btn">
</span>
</div>
</form>
</div>

In foundation you can use button styles in an input element maintaining its style concept, to use your submit button with foundation styles just use:

<ul class="right">
<form action="{{ path('acme_demo_search') }}" method="GET">
<li class="search">
<label><input type="search" name="q" value="{{ app.request.query.get('q') }}" /></label>
</li>
<li class="has-button">
<input type="submit" value="Search" class="small button" />
</li>
</form>

xavipirlo wrote:In foundation you can use button styles in an input element maintaining its style concept, to use your submit button with foundation styles just use:

<ul class="right">
<form action="{{ path('acme_demo_search') }}" method="GET">
<li class="search">
<label><input type="search" name="q" value="{{ app.request.query.get('q') }}" /></label>
</li>
<li class="has-button">
<input type="submit" value="Search" class="small button" />
</li>
</form>

Thank you, xavipirlo!