Custom Rewrite rules

functions.php

add_filter('rewrite_rules_array', 'mmp_rewrite_rules');
function mmp_rewrite_rules($rules) {
    $newRules  = array();
    $newRules['expertise/(.+)/(.+)/(.+)/(.+)/(.+)/?$'] = 'index.php?expertise=$matches[5]'; // use the 5th tax segment
    $newRules['expertise/(.+)/(.+)/(.+)/(.+)/?$'] = 'index.php?expertise=$matches[4]'; // use the 4th tax segment
    $newRules['expertise/(.+)/(.+)/(.+)/?$'] = 'index.php?expertise=$matches[3]'; // use the 3rd tax segment
    $newRules['expertise/(.+)/(.+)/?$'] = 'index.php?expertise=$matches[2]'; // use the 2nd tax segment
    $newRules['expertise/(.+)/(.+)/?$'] = 'index.php?expertise_type=$matches[2]';
    $newRules['expertise/(.+)/?$'] = 'index.php?expertise_type=$matches[1]';
    return array_merge($newRules, $rules);
}