TINT receives Tweets via the Twitter Search API. When querying the Search API the results that are returned to us will not always match up exactly with what’s visible on Twitter Search (Twitter’s online search tool). This is due to the fact that Twitter doesn’t always index every Tweet that is made in their Search API. As such, we occasionally won't be able to retrieve them.
Twitter states the following in their developer documentation:
Please note that Twitter’s search service and, by extension, the Search API is not meant to be an exhaustive source of Tweets. Not all Tweets will be indexed or made available via the search interface.
Typical reasons we have observed for Tweets not being indexed are when a hashtag is relatively new, or if one particular user uses the same hashtag a lot over a brief period of time. Also, new users on Twitter can sometimes not have their Tweets indexed for a while until Twitter has verified their accounts.
Additionally, when you first connect a Twitter hashtag (or Advanced query) in TINT their Search API will only return Tweets from the approximately the last 7 days. This is a limitation of the Search API that we cannot work around. However, once a Twitter hashtag connection is made in TINT we’ll continue to pull in content from that point forward.
For more information about how Twitter's indexing works when a query (connection) is first made, please view this thread from their community forum.
If you believe that your TINT is missing Tweets for reasons not listed above please don’t hesitate to contact Technical Support at firstname.lastname@example.org.