You can use your list to send a question or request to library staff directly - this is only visible to you (and other list collaborators) and the library, not the students.
To send a message, open the list from where you would like to contact the library and click on the text bubble icon located on the right panel.
A messaging panel will open up, showing you previously exchanged messages in this list. Add a message and click "Send".
Responses from the library will appear in this message panel - you will receive an email notification when a response has been added by the library.