I heard this idiom on TV twice yesterday so I thought I would explain it.

Pull some strings means to use your influence to get people to do something for you.  It is usually used in an administrative context.  Also, it implies that the people are willing to help because of the status of the person asking.  The idiom comes from pulling on the strings of a puppet to move it’s arms and legs.

As John’s father was a judge, he was able to pull some strings and get him out of jail.

Could you pull some strings and get me an interview at your company?

The movie star pulled some strings and got front row tickets to the concert.