Hi Dom,
You should be able to use this if you know the specific campaigns you want to operate on:
AdWordsApp.campaigns().withCondition("CampaignName IN ['Campaign #1', 'Campaign #2']").get();
Naman was close, but the operators he specified are for LabelSets. It seems our documentation is not quite correct though as it would seem to suggest that you can't use the IN or NOT_IN operators for CampaignNames:
Also, we don't support OR'ing conditions. If you specify multiple conditions, they are AND'ed together. So if you want to fetch multiple campaigns via their name, I suggest using the IN, NOT_IN, CONTAINS or DOES_NOT_CONTAIN operators (though CONTAINS and DOES_NOT_CONTAIN will only match or ignore a single String as you mentioned).
Hope this helps,
Alex