In my custom chat filter, you can pick which words are going to be filtered out of the message, and it will successfully filter them out. Whether there are symbols in between the messages or not the word will successfully be filtered out. But, if you use extra language characters it will not filter the word.
This inspired me to make my own chat filter, that blocks words based on how close they are to a filtered word. It filters better as you chat to it.
Hm, you should make it so it doesn't censor stuff like "Luck", and I know that setting the similarity under 25% would fix this, but it would also make the accuracy worse. Maybe using this along with my one in a single filter would be cool, with yours under 25% so that it doesn't have issues like this arise.
Consider Snap! Build Your Own Blocks. This is a much better one that uses whitelists rather than blacklists.
but then some things like this get filtered:
you can add them to the dictionary if needed 
well thats a pain imo