The Dhamma teacher I’m listening to is talking about anicca awareness. wouldn’t that be anicca suta??? In Pali… but he keeps saying something to the effect of anicca SUNYA
aniccasañña, perception of impermanence.
The modern commentary “Satipatthana, the Direct path to Realization” by Analayo is a more efficient overview of anicca than reading individual suttas:
“According to the discourses, not seeing the arising and passing away of phenomena is simply ignorance, while to regard all phenomena as impermanent leads to knowledge and understanding.38 Insight into the impermanence of the five aggregates or of the six sense-spheres is “right view”, and thereby leads directly on to realization.39 Thus the direct experience of impermanence represents indeed the “power” aspect of meditative wisdom.40”—chapter V.3 ‘Impermanence’
I think the point is to pay attention to different aspects of experience. Realisation about anicca follows naturally when we notice how bodily and mental phenomena come and go. It’s not so much looking for impermanence, it’s just looking.