As Martin wrote, the GSM Trial only has command line generated logs , no options in the GOS Admin Menu like commercial appliances. Anyway, those “Logs” are only more specified journalctl commands anyway. journalctl -f, does give you a full log. If there’s nothing to see, that’s because nothing is happening in the moment. I suggest, stopping and deleting the current scan, starting journalctl -f and then starting a new scan. This way you see everything that happens right from the start.
(Also when a scan “stalls” most time it’s being ignored by something on the target and waits for a time out.)l