同时设置两个 Bootstrap nav menus

For your first dropdown

<a class="btn btn-navbar" data-toggle="collapse" data-target="#first">

For your second dropdown:

<a class="btn btn-navbar" data-toggle="collapse" data-target="#second">

Then you can add that unique id to your nav collapse container:

First

<div id="first" class="nav-collapse"> ... </div>

Second

<div id="second" class="nav-collapse"> ... </div>