Use this code bellow to dynamic you nav:
<?php
$args = array(
'theme_location' => '',
'menu' => 'Main',
'container' => 'false',
'container_class' => '',
'container_id' => '',
'menu_class' => 'cs-main-navigation cs-clearfix',
'menu_id' => '',
'echo' => true,
'fallback_cb' => 'wp_page_menu',
'before' => '',
'after' => '',
'link_before' => '',
'link_after' => '',
'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
'depth' => 0,
//'walker' => new my_custom_walker_nav_menu()
);
wp_nav_menu ($args);
?>
</nav>
<!-- Search icon show -->
<div id="cs-header-menu-search-button-show"><i class="fa fa-search"></i></div>
<!-- Search icon -->
<div id="cs-header-menu-search-form">
<div id="cs-header-menu-search-button-hide"><i class="fa fa-close"></i></div>
<form>
<input type="text" placeholder="Type and press enter...">
</form>
</div>
</div>
</div>
</div>
For more details please see This ….. Hope it will solve your problem