You can search for any term, including a URL, keyword, hashtag, phrase, Twitter name or combination. Shorter queries work better, so keep your search terms under 70 characters and/or 6-8 total words. 

TweetReach supports most advanced search.twitter.com operators (except “near”). In addition to searching for any term or URL, you can also limit your search by date, exclude certain terms, chain together terms, use OR, and more. Some of our more commonly used search options are:

• term1 term2: search for tweets containing both term1 and term2 in any order
• term1 OR term2: search for tweets containing either term1 or term2
• “term1 term2”: search for tweets containing the phrase “term1 term2”
• term1 -term2: search for tweets containing term1 but not including term2
• from: to search only for tweets from a specific Twitter user (e.g. from:briansolis)*
• to: to search only for tweets directed to a specific Twitter user (e.g. to:briansolis)*
• since: to search only for tweets after a specific date in UTC (e.g. since:2010-03-30)
• until: to search only for tweets before a specific date in UTC (e.g. until:2010-03-30)
• filter:links to search only for tweets containing links
• source: to search only for tweets from a specific Twitter source (e.g. source:tweetie)
• lang: to search for only tweets in a particular language (e.g. lang:en for only English tweets, more info about languages here)

You should also consider common misspellings and alternate combinations of your search terms in order to fully capture the concept you're measuring. Also consider if it would be useful to search for an exact phrase (if so, use quotation marks) or words appearing in any order (do not use quotation marks). 

Since we can only pull back approximately 1500 tweets from Twitter, if you're searching for a popular term, consider running reports frequently to get as much data as you can. Also, Twitter is currently limiting its search API to results from only the past few days, so be sure to run your report before your results disappear. 

Long queries probably won't work. Instead of pasting in the entire text of a tweet, choose a few important words from the tweet to search for. Limit your queries to 6-8 words maximum and you'll get better results. 

*For more information about finding tweets from or about a specific Twitter account, read this.