Is it possible to search for text by the date/time it was added?
Topic on Help talk:CirrusSearch
That's not possible with the (old or new) site search, as it only searches the current revisions.
There is an external tool which aims to support this, although it is fairly complicated (for me at least) to use initially (I forget how it works, and have to re-learn via experimentation, each time I use it). See en:WP:WikiBlame for links and details.