What is Ilm al Riwayah and Ilm al Dirayah?

Ilm al Riwayah: A study of the chains of narration (sanad) in terms of the principles related to the conveyance and transmission of Hadith.

Ilm al Dirayah: A study of the chains and texts in terms of the principles related to the acceptance and rejection of reports, along with understanding the meaning of its words and overall context.

And Allah knows best!