<link href="//netdna.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<div class="container">
<div class="row">
<div class="input-group input-group-lg">
<input type="text" name"search" class="form-control" placeholder="Search term...">
<div class="input-group-btn">
<button type="button" class="btn btn-default" data-toggle="dropdown">Advanced <span class="caret"></span></button>
<ul class="dropdown-menu pull-left" role="menu">
<li><a href="#">Option 1</a></li>
<li><a href="#">Option 2</a></li>
<li><a href="#">Option 3</a></li>
<li class="divider"></li>
<li><a href="#">Option 4</a></li>
</ul>
<button class="btn btn-default" type="button"><span class="glyphicon glyphicon-search"></span></button>
</span>
</div>
</div>
</div>