I regularly find tweets (with working https://t.co/TigDLjoHkY links) in my @mhawksey designed twitter archive that fail to show up in Twitter's search/advanced search.
Is there a super advanced search I am missing, or is this Just Another Broken Twitter Thang?
I have not really searched through my archive. However, I have found that the RSS feed provided by Granary provides Tweets even if they no longer exist.