Sorry, this is not possible. You can import the pages only from the other demos not the content or products from the other demos.
You can do it by manually, install the theme on the staging or test site then import the demo on that site and then export the products from test and import them on the live site or wherever you want to import.
I tried importing the demo, but only a few products came through. The demo theme includes many products, and despite several attempts, I’m still facing the same issue. I really need the demo products, so could you please provide me with the export files for the demo products?
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