How did he get the CV-s of his competitors?

That was a nice thriller with a touch of black comedy. The one detail I didn't understand was: how did he get the resumes (CV-s) of his competitors? At the very beginning f the film, he told something to the postal office lady, something about some number, and that's how he was able to get the resumes of the people who had applied for the same job. But what exactly happened there? I didn't get it.