Listing wordpress users with a search function

This worked for me.

$user_query = new WP_User_Query( array(  'search' => '*example.net*', 'search_columns' => array('user_url') ));
$authors = $user_query->get_results();

The wild card to be used in the search string is ‘*’ and not ‘%’. Also you have to include the ‘search_columns’ parameter with the following possible values

search_columns = array( 'user_nicename', 'user_login', 'user_email', 'user_url' )

Importantly, these are the actual field names from the users table. I tried my above mentioned query using 'search_columns' => array('url') and it failed.