While ⌘ + Tab-ing, hold down command (⌘) and press the arrow up or arrow down when an app with multiple windows open. You can then select which image to open.
You can also press H to hide/show the selected app
How to Switch between multiple windows of an app when ⌘ + Tab-ing
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How to Find a file in Finder from Spotlight
With a Spotlight search open find the selected file by clicking Command + R.
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9 Mac Tips and Shortcuts You Should Know
Useful Mac tricks including window management, Spotlight shortcuts, trackpad gestures, and system preferences tips