Specific sites have their own searching capabilities. PE-Talk has an archive search available. This can be used to find what has been written on topics. At ERIC , the Educational Resource Information Center, you retrieve citations and abstracts for education-related literature relevant to your search topic. This site is one of the most comprehensive sites available.
Most search engines allow the use of boolean operators.
AND' searches for material that contains both words in the search, such as children AND sport. OR' searches for material that has one term or the other, such as children OR sport. NOT' searches for material that has one term, and not the other, such as children NOT sport. This limits searches to material that contains one topic, but not the other. Whether information is from books, periodicals, on the Internet, or other sources, the material can not be assumed reliable.