Job Offer - Assignment Info flexfields in OTBI report

Summary

How to find Job Offer - Assignment Info flexfields in OTBI report

Content

Hi,

I want to build an OTBI report in which job offer information for each candidate are shown.
In particular, I need to show in this report information that are collected in flexfields in the Assignment Info section of the job offer. This flexfields belongs to the Core HR area (Assignment attributes, flexfield code: PER_ASG_DF), and are inherited by ORC in the job offer page, Assignment Info section.
So, I am using for my report the Recruiting - Recruiting Real Time subject area, but I cannot find these fields that I need, even searching in the Job Offer > Job Offer - Assignment Details folder.