During each session in Primo, your searches are recorded in the Search History, so that you can reiterate them.
If you are signed in to Primo, you can save any search from the Search History of the current session by clicking on the pin icon. That way you can repeat that search in future sessions at any later point in time.
You can have Primo send you alerts when there are new sources in the database that match your query.
Note: Unfortunately alert functionality is currently not running satisfactorily for books in Freie Universität libraries: To some degree, alerts will include not only new acquisitions, but also dated publications that you have already taken notice of.