使用AngularJS中第一个API的响应调用多个REST API

I am new to AngularJS and trying to make an application which loads data by calling APIs. It is like I am fetching the list of boxes of type A (Resource Groups) and then each Box of type A has multiple boxes of type B (Virtual Machines). So I have been able to fetch all type A boxes and by using each value of type A box, I have been able to fetch all type B boxes(VMs). But now how shall I put the VM's in respective resource group's panel-body.I am new to AngularJS and trying to make an app