We are thinking right now about adding a more detailed date filter. Instead of just refining the search via the existing categories (last week, month year etc), a user would be able to specify a start and end date.
We are planning this feature for a lot of content types.
This feature has been deprioritized in our roadmap.
Unfortunately, we need to postpone this feature further to speed up the development of our Office365 integration. However, we understand that a lot of users demand this and the topic has a high priority. We have therefore kept the item on our immediate roadmap.