I am sorry to hear that your device has been stolen.
Unfortunately, logfiles are for support and diagnostics of the application by our support team. Because of this, we cannot teach you how to use the logfiles (Even our supporters use specialised software to read them)
In this case, I can confirm however that the IP address is not stored in the logfiles as TeamViewer connections are end-to-end encrypted.
TeamViewer is not tracking or anti-theft software, so we cannot provide assistance here sorry. We would recommend you contact your local authorities.