He Knew the Question Already

Two of my friends had similar incidents. One of them prepared a question on Sefer Yetzira. He approached Reb Moshe and before he could even formulate the question, Reb Moshe responded, “Ah, you are asking about the Sefer Yetzira?” And my other friend had a question on Rabbeinu Bachaya and the same thing happened: he approached and after saying the beginning of the question, Reb Moshe knowingly interrupted him saying, “Ah, the Bachaya?!” as if somehow he knew what question they were about to formulate and ask him before they had done so.