If you want to see the list of projects a staff has been assigned to, you can use the People Explorer Report :)
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1. Go to Reports > Explorer
2. Turn on the Detailed Toggle - this will give you the list of projects that the staff has been assigned to

3. Select the Date Range - you can set the start date to as far back as you want

4. Type the name of the staff in the person Filter

5. Click the mini arrow to the left of the person's name - then you should see the list of projects they were assigned to during the specified period