When documents are uploaded to the File Management system, no extraction occurs on those documents. They are simply being stored in AutoEntry at this point.
AutoEntry therefore does not know any of the data contained in those documents, including the document date. AutoEntry will only display the date the file was uploaded.
For ease of retrieval later, or to aid searching for old documents, you can set a document date using the calendar option once the file has uploaded. Simply click on the document date field and enter the date for the document.
To retrieve documents from a certain date period, you can then use the 'Choose dates...' option to the top right and filter the results by document date - either by selecting a preset 'Last 30/60/90 days' or selecting the start and end date manually from the calendar displayed.