filter custom field with checkboxes and show it with one shortcode

add_shortcode( "Querbett", "bettenaert");
add_shortcode( "Alkovenbett", "bettenaert");
add_shortcode( "Queensbett", "bettenaert");
add_shortcode( "Hubbett", "bettenaert");

function bettenaert (  $atts, $content = null, $tag ) {

   modell_nach_bettenart_2( $tag );

}

Now use shortcode [Querbett], [Alkovenbett], [Queensbett] or[Hubbett] as required.

I hope this may help.

tech