The current .NET version of Aspose.Pdf.Kit could not support the feature of searching specific text in a Pdf document, but the feature is on our roadmap, and I hope we could support it in this December.
We will inform you in this thread when searching text could be supported, and we will also investigate how to better support adding/editing links according to your requirement.
By the way, you mentioned the "paragraph ID" about which I don't know, could you elaborate it?
About the paragraph ID, in the Aspose.Pdf tool, each paragraph object has an ID property that is a String and any item can then be retrieved by this ID.
I don't know if this ID is just used during the creation of the PDF, or whether it is retained in the PDF once created.