If you're referring to a general topic of Usul al-fiqh (the principles of Islamic jurisprudence), here's an overview:

For those studying the text, Sheikh Wal Asri provides a series of lessons in Afaan Oromoo . 2. Usuulal Fiqhii (Foundations of Jurisprudence)

The book is structured around the three fundamental questions every Muslim is believed to be asked in the grave:

(often referring to Usuulu Salaasa or the "Three Fundamentals") is a foundational Islamic text widely used for teaching the core principles of faith, particularly within the Oromo-speaking Muslim community. In its PDF form, it serves as a critical educational resource for students of knowledge ( Talabul Ilm ) seeking to understand the pillars of Tawhid (monotheism) and the essential questions every Muslim must answer. What is Kitaaba Usuula?

Digital versions in are widely used for self-study and community teaching:

These texts are the backbone of orthodox Islam. Without a teacher (or at least a recorded commentary), it is very easy to misinterpret a term like Harf (letter) or Qiyas (analogy).

Tawheed (Oneness of Allah), Prophethood, and the Pillars of Islam Primary Sources Based on the Quran and Hadith (notably Surah Al-Asr) Key Sections & Principles