You can use the Files tab in a space to view all files that have been shared in the space from a single screen.
To view files shared in a space:
Click on the space you wish to view files for
Click on the Files tab along the top of the space
Click on the Drive button next to a file to add it to Google Drive - if the file has already been added to your My Drive, you will see a folder icon that can be clicked to move the file to another location
Click on the Chat button next to a file to open the chat message that the file was originally added to in the space
Click on a file to open it