From your twitter home page (http://twitter.com, assuming you’re signed in):
There’s a search box on the right hand side of the page:
The results will appear in a list:
You can save this search to your page by clicking on the Save this search button at the top of the list:
The search will be added to a list below the search box on the right hand side of the page:
To search from outside your profile—meaning you don’t have to log in, or have an account at twitter, go to search.twitter.com.
You’ll see a Google-like interface:
Searching this is the same as the search above.
But you can make a more complex search by clicking on the Advanced Search link:
This page will allow you to narrow your search down by words, hashtags, people, places, dates and something called attitude (positive, negative, or whether the twitterer is asking a question).
The places feature is particularly useful, enabling you to narrow down searches by location. (Although it’s not foolproof. Most places are taken from the profile, and so can be faked. Some, however, are taken from geolocation services, especially if the twitterer is using their mobile phone, and so are more reliable.)
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