Multi-value fields (e.g. checkboxes) are output with binary field separator bytes
I know it says "raw field" but this is very raw and includes CiviCRM's binary field separators.
Suggest these are removed and replaced with commas (or spaces etc.)
e.g. to reproduce, add a custom field that uses checkboxes to allow you to select more than one item from a list, then view it in the data processor search output.