I've never used SOHO notes, so can only give general advice here:
Does SOHO notes give you options for exporting the data? (Most such apps do.)
What file formats can SOHO export to?
Chances are there's a common file format that SOHO can export to and Filemaker can import from. Find that format and you've got what you need.
Common file formats that are often used for such data exchanges:
Text, Tab delimitted text, CSV (comma separated values), excel files, DBF, XML
and filemaker can import from all of these file formats.