Adding a custom field to Ultimate Members directory search options

filter.php

add_filter('um_admin_custom_search_filters','add_my_custom_search_fields', 10, 1);

function add_my_custom_search_fields($fields) {

	$fields['field_meta_key'] = array('title' => 'Enter field title'); // replace 'field_meta_key' with your field meta key
	return $fields;
}