In general, they taught military intelligence (they may have taught more than that but MI is what they were known for). To be more specific, you'd have to know his specific MOS and then look into what that MOS was taught during that time after WWII and during Korea. More specific than that wouldn't be appropriate for this venue.
I went to my AIT there in the early 60's for 96B(intel analyst). If memory serves me OK, interogators also went there. I'm sure there were more MOS's trained there, but just cannot remember