Here's a list of different ways to cycle through your open drawings within a single AutoCAD session.

• Window menu pull-down has a list of open drawings listed at the bottom, click on the drawing to switch as current.
• Ctrl+Tab to cycle through your to the correct file.
• Ctrl+F6  to cycle through your to the correct file.
• Set the TASKBAR variable to (1), on, to show all your open drawings on the Windows Taskbar, click on drawing to switch as current.
• Click on the AutoCAD icon just to the left of the File menu pull-down and either select the next listing or type T to cycle to the next drawing.