To see feedback from a specific student there a two options.
Choose the assignment you would like to see by clicking on the Assignment title on the sidebar. Then click on the Results tab. You have 2 options, to view a submission and it's feedback (submission tab) or see all the feedback that 1 student gave (reviewers tab).
On the left side you will see a list of all the students. Scroll down and click on the student that you would like to view. This will display their feedback on the right side of the split screen.