Yes, It is possible to search all activities corresponding to a particular user/group (Object history and actions done by the user). You would find a "Search" option at right top corner. Once you click, you would be prompted to search and enter a user/group and this feature exactly displays all logon activities/changes happened to the object and AD changes performed by that object, however the result does not include the file/folder changes.
To have an aggregated view of all changes that a user/group is involved, we could create a custom report having all modules and required filters added to it. Please refer below steps,
1. Go to Reports tab
2. Click on 'Custom Reports'
3. Create New custom report
4. Enter a name and description
5. Select the view
6. Select all modules and sub modules under report category
7. Once clicked on next, select the columns to be displayed
8. Under Filter, Add the following filter,
User Name -- Equals -- <Username>
9. Save the report
Hope it helps.
Regards,
ADAudit Plus Team