How could I see my YouTube liked comments?

Hey,

This is a bit manual job, You need to check out each and every video's comments on your YouTube Channel.

Else you will get such things on some analytics tool like Vidooly, where you can find your influencers, most engaged comments, unsubscribers and many more.

Best,

You can't unless they share it on google plus. Even still if their profile is private you wouldn't find it there either. It isn't maent for you to be able to find them.

I am not able to get your question clearly but what I can understand is how you can see the comment you have liked on any videos.
You can view your activities on YouTube on your Google+ page.
YouTube comments are now a part of Google plus.