A few things to try (you might have already done these):
phrases should in quotes
not foo bar
all words / phrases should be lower case
you might also try placing each word / phrase on a new line
If this doesn't work, let us know what version of Clearspace you are running, and we'll take another look at it.
I've tried all combinations of quotes (single and double), with commas, with new lines, with commas + new lines, and I'm having no luck. And as you mentioned, all words in the list are lowercase.
I am running ClearspaceX 1.5
Any progress on this?
For these types of cases, it might make more sense to use the RegExp filter, as that might give you a little more flexibility in what words are filtered out.
Check out the following JIRA issue: