Until recently, if you wanted to find the location of your document, or place your document in a specific in Google Documents (including Sheets, Slides and Drawings), you would have used the folder icon which was located next to the Document name (see image below).
It allows you to view the present location of your document, move it to a new location or add the file to an additional location.
Adding the file to a new (additional) location is something that many beginner/intermediate users can struggle with when moving from more traditional environments like Windows and even OS/X. (I will be doing a separate post about this fantastic feature in the future).
If you wish to add the file to a new location, simply hold the command key if you are on OS/X or the control key if you are using a Windows based machine as you click the additional location.
Hope this helps you!