Issue
Did you mean? suggestion returning undesirable results.
Resolution
Unfortunately, Did you mean? feature is not configurable.
It self-learns based on corrections done by users, when an initial search doesn't return a result, and then a subsequent search by the same user in the same session, returns a result.
There is no way where we can configure this to exclude certain words.
You have to turn off entirely .
Here is the document how you can turn off this feature entirely:
https://docs.servicenow.com/csh?topicname=t_ConfigureADidYouMeanSuggestion.html&version=latest