Information on syntex

[i4th8]

Is there any documentation on SharePoint Syntex?  I am trying to make a model to understand resumes nothing fancy yet just trying to figure out what it can do. I have not found any guidance as to syntax it is looking for or anything like that. 

I found some documentation here https://docs.microsoft.com/en-us/microsoft-365/contentunderstanding/create-an-extractor?view=o365-wo... but it is very sparse.

[#2]

Also, to be useful this really needs to be able to take regexs. Without regexs doing something simple like extracting a contact email is almost imposable.