extract document type from folder

With Finder Preferences to Search Current folder,

Open the topmost folder and enter the file extension into the search field. All of the matching files should be listed in the window. Select them all and move them to wherever you would like.

If you want to move them to another volume, like an external drive, you need to hold down the command key while dropping them so that they will move and not copy. If you are keeping them on the same drive, then just drag and drop.

You can use Find Any File to search for any files with the appropriate extension on the volume you need to search. For example:

1 - Name contains xlsx

will get you these results:

Any files that are found can be dragged from the search results window to a folder on the Desktop or or wherever you want.

FAF can search areas that Spotlight can't like invisible folders, system folders and packages.

OR you can do it with Spotlight. Just open a new finder window and use the key combination of ⌘+F. Then use the following criteria:

Again you can drag from the search results window to a folder located anywhere you'd like.

Spotlight can't do a "does not contain". But Find Any File can:

To add additional groupings for And, Not, Or, hold down the option key and click what was the + button.