How to use an Global String as an ID to list a certain data

I have created a Class method to list employees that are subordinated to a certain boss. But I don´t know how to relate the data in the way it was given to me.

For Example:

• ^Employee(IdEmployee) = Name

                  ^Employee(1) = "Jessica"

                    ^Funcionario(10) = "Rose"

• ^HistEmployee(IdEmployee, Date) = Salary^Job^IdEmployeeBoss

                    ^HistEmployee(10, 64628) = "3500^Secretary^1"

So, based on this seetings, Jessica is Rose's boss. But I don't know how I can make a relation between that string and the subscript. Can someone help me?