Creating variables from AppDynamics Metric

Hi Experts. I am new to Grafana. We are working to create Dashboards for our Infra. Our Data source is AppDynamics. So, when I click each time ‘select metric’, my next dropdown is appearing for selection. I would like to bring one of the metric segment into a Variable. How to refer a segment of a AppDynamic metric in the variable query? For example, I need the 3rd segment of the metric into a variable.

Please let me know.