If I understand your question properly, you’re trying to use the “Exclude Pattern” to exclude certain values from populating in the chart.
The “Exclude Pattern” and “Include Pattern” fields are for Regular Expressions and are documented here: http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html.
If you want to exclude multiple fields, you could do something like this:
term1|term2|term3