$query = $connn->prepare('SELECT * FROM table_users WHERE user_name LIKE ? OR user_address LIKE ? OR user_note LIKE ?');
$query->execute(array('%'.$user_name.'%','%'.$user_name.'%','%'.$user_name.'%'));
Hepsine $user_name dedim mesela. Post ederken de tek post ile yaptım.
$user_name= $_POST['query'];