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If you need to search for a specific date range select any option from Date modified & then click in the search box to see a calendar
Alternatively you can edit the date modified to search for anything older than a specific date. Type <(date) after datemodified: in the search box (so it looks something like datemodified:<01/01/2015)
When you see the results of a search you can open or delete files directly. If you need to see their location click on the View tab & select Details,