To restrict the data users can search, you can tell the indexer not to index certain pages. When a page is not indexed, it cannot show up in search results.
For example, suppose you have created a series of HTML files called finance_report_q1.html, finance_report_q2.html, and so on, which you have checked into the reports directory of your project. These documents need more work, and are not ready for general viewing. You are concerned that people from other parts of the organization may come upon these documents and get incorrect information.
To make these documents invisible to the search engine, follow these steps:
Disallow: /reports/
Now, if someone on the domain searches for the keyword "finance," the search results do not show the reports directory containing your draft documents.