Relating columns based on choice not sure if I'm wording this correctly.

I made a Job application form, each applicant applies to a vacancy ID and each Vacancy ID is supposed to be attached to a manager. So when the notification goes out its supposed to alert the manager, but I cant figure out how to make them connect. ex one list is the application where there is a lookup column for the vacancy ID and I have a vacancy ID list that has the manager column and the Vacancy ID column. when they choose a vacancy ID on the application, I would like the manger to be notified wtihin the workflow notification that John Doe has applied to your vacancy.