Searching by title, content and custom taxonomy

[WP_Query][1] provides list of options including [Taxonomy Parameters][2]. You can use the taxonomy parameter to search the posts like:


post_type' => 'firma',
'post_status' => 'publish',
'order' => 'DESC',
'orderby' => 'date',
's' =>$_POST['term'],
'posts_per_page' =>5
'tax_query' => array(
    array(
        'taxonomy' => $_POST['term'],
    )
);