When you first log into the care portal or go to the "Home" tab, you can see all of the accounts you are assigned to.
How to Search for an Account
Type in any part of the Account name, then press the Enter key (or click the Refresh button.) A shorter list of accounts will appear, with only those accounts whose names contain the characters you typed. To display the whole list again, clear the search box, then press the Enter key (or click the Refresh button.)