Any closed ticket with no updates for the past 120 days would be marked as Archived. These tickets would be part of the archived tickets list on your helpdesk.
Please go to the Tickets tab and click on the view list > choose Archive (under the 'List View Names' dropdown) to see all the archived tickets in the portal.
Alternatively, you can access the archived tickets by performing a search in your helpdesk or by directly hitting the ticket ID in the URL. Under the Global search, if you want the Archived tickets to show up, you have to manually change the search settings to include the archived tickets if required. By default, this option will be turned off.
If you are using Freshdesk on Mint, clicking on the Archive view will take you to a page where you can apply the required filters and then export the file to your agent mailbox.