We had the same issue, but solved it by adding in rules and restrictions in our Visualizing software. We basically created a "not accepted" list of key words that would get automatically NOT get displayed.
If that's not an option perhaps you should consider rephrasing the question so people are less encouraged to actually write something if they do not have valid feedback.
Perhaps something like "This is how [company] can improve my experience" or something?

All the best
-Mattias

Thanks for your feedback MattiasM . I suppose that this Visualizing software was then something else than the Text iQ bubble charts in the Qualtrics dashboards
Lately we've indeed been rephrasing towards questions like "what can we do to improve" etc, so hoping we won't have the issue going forward then.

Hi JoycaV , MattiasM
For excluding the word, you can use "no" or "No" i.e. apply inverted commas as it will take only the word no and not the phrases.

Hi Chhavi_Ch,
unfortunately, even with "No" between the quote marks, a full phrase such as "there is no fridge" is still selected, becuase the word "no" litterally appears within the phrase.

-"not" && good