I don't think you can see the plate, so I will provide a screenshot of it here https://gyazo.com/d1919d102eb3d064ab17efb5b7a9f68d
TAZ buses were built in Zagreb during the Yugoslav era, with several models, they were semi-common in Yugoslavia.
With the breakup, they have almost completely disappeared off the roads, its extremely rare to find one now, in fact there isn't even one in the Croatian gallery.
I dug up that photo on my old photos, so that one is from 2011, however the fact that you have managed to find another one is an incredible achievement, good job.