I stumbled on this problem after being frustrated with tagged articles not showing up in search ONLY because the tag used hyphens. Actually even w/o tags any word with hyphens in it won't get recognized. Though the given term was in the title and multiple instances in the body text, it doesn't show in Search.
FD support told me this was a design decision to exclude 'special characters' from search. Wow, this was very surprising to hear. This was a bad decision IMO given the very common use of at least hyphens in product and technology names such as Wi-Fi.
All product names in my company uses hyphens and that's how they're referenced in all communications yet when you search for those product names in our FD portal the results are zero.
Any good search tool is very forgiving in what the user searches for. Look how good Amazon is with misspellings.



