Use a set of quotation marks around phrases such as "educational theory" to prevent Google or other search engines from inserting an AND between the terms.
Truncate search terms with an * to increase the number of results, i.e. educ* will retrieve sites with education, educational, educator, educating, etc.
Limit your search by domains to increase the chances of retrieving pertinent results, i.e. site:edu, site:gov, site:org
* Establish policies on federal financial aid for education, distribute, and monitor those funds.
* Collect data on America's schools and disseminate research.
* Focus national attention on key educational issues.