Try using an image enhancement tool (like ScanKromsator) or simply increase the contrast on your PDF reader. Alternatively, check Archive.org for a different scan—multiple users often upload different copies of the same antique book.
Alternatively, maybe it's a modern compilation. Let me try to find some information. A quick search in my mind: "Jawahir Rasail PDF" – maybe it's a PDF version of a book by a contemporary scholar. Or perhaps it's a compilation from the writings of a specific Sufi order, like the Naqshbandi or Chishti.
Alternatively, maybe it's related to the 12th-century scholar Ibn Abidin Shami, but I'm not sure. Alternatively, maybe it's not a specific scholar but a general collection. I need to check some sources. Perhaps looking up "Jawahir Rasail" in scholarly databases or Islamic websites.
Jawahir al-Rasail (Precious Gems of Letters) is a collection of essential letters and discourses by , a prominent Senegalese Sufi scholar and leader of the Tijaniyya movement.