Working on Multiple Workbooks in Excel 2013

Hello Everybody....

I have been working on excel 2010. There was a very helpful feature in excel 2010: While working on multiple workbooks, one could see two sets of "minimize, restore, and close buttons; upper one for main window of excel and lower one for the active workbook out of the workbooks openedand being worked on. Using lower set of buttons one could minimize, restore or close any of the workbook without closing the main window of excel. And if one of the workbook was minimized it could be seen like a small ribbon in the bottom of main excel window where one could restore or close this workbook. One or more workbooks could be opened and worked on within the main window of excel. Now I am working on excel 2013 and I want to use this feature but I am unable to do this. Could any one please help me on this.

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