If your Workspace is using the Teams feature, when you create a Space, it will connect to the Team you created it in by default. Any time you select that Space, it will switch you to that Team and show you the filtered stories for that Team only.
For example, if you create a Space while in the Product Development Team, it will automatically connect to it, and clicking on that Space will always switch you to viewing filtered Stories within the Product Development Team.
If you wish to connect or disconnect them from a Team, you can do so in the Saved Space's menu, under More Actions.
Any time you create a Space (and choose to disconnect it from its Team), it will just surface Stories that meet the Space's filters you have set in the Team you're currently viewing.