How to find a selection of photos taken at different dates but imported together. I want them in the same album but they're no longer in the "last import" album.

Sorry I'm terrible at explaining and even using my macbook haha. Let me try again. I imported some photos that I wanted to group together into an album. I forgot to create the album before importing a new set of photos which then took the place of the previous ones in the "last import" album. Is there anywhere or any way I can easily find the selection of photos I forgot to put into an album together without having to select them one by one from the "all photos" section? These would be the only pictures in my Photos application that haven't been organized into an album yet if that helps; however, these photos were not taken on the same date.