What does 2 Kings 5:20 mean?

But Gehazi, Elisha's servant, thought, 'My master let this Aramean off too easy by not taking anything from him. As surely as the Lord lives, I'll run after him and get something.' 2 Kings 5:20 - Modern Text Bible

(Gehazi, Elisha's servant, is greedy and thinks Elisha should have accepted a reward. He decides to chase after Naaman to get something for himself.)