The SS search utility can be made to work (using appropriate stop words) to answer searches phrased as questions, but an attached question mark causes it to fail.
This works: "How do I fax an order"
This works: "How do I fax an order." (period at end)
This works: "How do I fax an order ?"
This doesn't work: "How do I fax an order?" (attached '?")
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Note that FAQ items can be added to search by setting up your FAQs as a product and carefully selecting a multitude of keywords.