Person criteria - not able to add more then one position

Summary:

Hi all,

From my Client Group > Learning > Course > Selecting a Course > Learner > Add learners > choosing person criteria in the "select learner" step > Advanced, I would like to be able to enter more than one position. I can add the other fields, like “business unit,” as many times as I want to assign learning to all employees who are in at least one of the selected BUs. Instead, I can only add one position, why?

Thank you,

Alessandro.