how can I edit the 'Who can enroll' text

Hi there,

When you view Courses on the actual website, there's text 'Who can enroll:'

This shows the the options Anyone.......

I need to edit the 'Anyone' option, so it's Anyone (18 years or older)

I already tried editing the .po files with POEDIT, but it doesn't work.

How can I do this?

Thank you