nDepth is usually only going to return about a week or two of data before timing out.
You can use the Database Maintenance Report to check the database retention number in days, then run a search (or a report) for the tail end of that time frame to confirm the data.
Depending on the size of your disk and how much your environment logs over 365 days it could be anywhere from 250 GB of data and up, there's just no way to return all of that in a single search or report.