You can search either the "My CaseFolders" or the "Firm CaseFolders" view by using the search box at the top of each view.
For example, navigate to your "My CaseFolders" view as shown below:
Begin typing a case name or number in the box and the search will execute as you type.
TIP #1: The search box shown above works with partial case names and numbers so you do NOT need to fully enter anything.
TIP #2: You do not need to click the "Search" button; after you start entering a case name or number, it will start searching. It is best to pause for half a second after you've typed enough to identify your case.