When you open a file from HoudahSpot, HoudahSpot passes along the text you searched for to the next application. This allows other applications to highlight the text or let you search for it by using Edit > Find > Find Next.
This happens if you search by "text content" or "any text" or using the search field at the top of the window. It does not happen with text used to search by name: you expected to find that in the file name, not the file content.
Some applications do not support this. HoudahSpot keeps a list of problematic applications and avoids passing text to those.
Word is not one of these applications. HoudahSpot however does give Word a special treatment to work around a bug that existed in betas of Word 2016. I don't know if that workaround is still needed. It may even be what is causing the problem.
Which version of Word are you using?
Please try searching for a file by name only. Does opening the file in Word work as it should?
Please check /Applications/Utilities/Console.app > All Messages for error messages from HoudahSpot or Microsoft Word.
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