Sel ect the filter and press the 'add condition filter'

However, if you want to filter the messages fr om a set of senders then I wouldn't add all of those addresses to a filter.
Create a filter that checks whether the sender is in an address group, the condition should look like this:
address group - friends - contain - sender
This is supposing you've got and address group friends.
Now when you want an additonial contact to be processed by your filter then you add him to your address book and to the group friends, if he's already in your address book then you only need to add him to friends.
When his address changes then you only need to alter it in your address book (especially with friends it's likely that you want to update his contact info in your address book) and your filter will be updated automatically.

Note that the address book might give you unexpected results when you got multiple address book entries with the same email address. (But you can add multiple addresses to the same address book entry without problems)
One address book entry can be part of multiple address groups, they're not really groups, but more like labels.