You can see the comments on a clip by going to the Review application. In the Flow Library, click on the three dots on your clip and click "Review" as shown below. 

This will show you all the comments made on that clip.

Tip: if you have made comments on your subclips, then you can search for those comments in the search bar. In the screenshot below, you can see for example that we searched for the word "interessant" and Flow shows you where the word shows up inside the subclip (the blue dot represents where in the subclip this comment was made).