Twitter Search API is a dedicated API for running searches against the real-time index of recent Tweets. The Search API is not complete index of all Tweets, but instead an index of recent Tweets. At the moment that index includes between 6-9 days of Tweets. You cannot use the Search API to find Tweets older than about a week.
Step #1 login
To get started login to your twitter account
Step # 2 type the keywords and search
On the twitter search box type the keywords of your choice and search. Results with the keywords you have typed will be displayed.
Step#3 choose embed this search
Click on the gear button on your left, and choose embed this search. You will be redirected to another page to configure your search widget. This allows you to add any public Twitter timeline to your website.
Step#4 customize widget
Once you are done customizing your widget, click create
Step#5 Paste the code on your site HTML
A code will be automatically generated. Simply copy and paste the code in the HTML of your web page. Some websites will display everything while some will give you a link that redirects you to your twitter search. You can perform different searches and embed it to your blog. You can learn more on how twitter API works by visiting twitter developers site.