// Add an additional submenupoint
add_action('admin_menu', 'register_mycustom_menupoint');
function register_mycustom_menupoint() {
    add_submenu_page( 'woocommerce', 'Name on Menubutton', 'Name on Menubutton', 'manage_options', 'custom-submenu-page', 'dsrv_init_backend' );
}

function call_this_function_name(){
    // ...
}