Time and again, I have seen people making comments (polished and polite) here which I think I could borrow and use at other relevant places later because I often feel like I am at lack of words and probably won't be able to vocalize my opinion on a question/post in a polite and humble way. I have tried to search for some of them (which I really liked the first time I saw them) but it just gives too many results and it would take a ridiculously long amount of time to search through all of it just to search for a single comment (I forgot to save them at the time when I first saw them but when I face the same situation, I believe their comment (which I read a long time ago and vaguely remember) would have been appropriate and succinct to say in that situation). Also, I checked out the user's profile but it seems there is no way to check their daily activities(the comments they make on a particular day). By the way, I am not trying to stalk any user in particular, so please do not get me wrong. Is this possible to view comments made by someone? or is that a privilege one needs to earn? or is it not possible at all? Also, what do you do in a situation when you know the answer to a question but still find it difficult to write it down without making it look like it's been written in broken English with a very clumsy use of words.
You can reach a chronological list of the comments left by a particular EL&U user from the user's Profile page, in three clicks. First click the Activity link in the upper left corner of the Profile page; then click all actions in the row of links beneath the Reputation, Badges, and Impact summary boxes; and then click comments in the row of links that appears immediately below 'all actions'.
I believe that there are no reputation-based restrictions on access to a user's comments or to any other linked data field in a user's Profile or Activity summary, though I may be wrong about that.
If you know, or are willing to learn a bit of, SQL, there is https://data.stackexchange.com. You should be able to get a query that targets a specific user, where you can find comments containing keywords and within specific timeframes.