However, good answers will be included in the answer set. Both concepts present anywhere in the reference . This is equivalent to a Boolean AND, although the two words in each concept may not be adjacent. This group usually includes additional useful references. These last 2 search results are rarely useful, unless the question includes very specific concepts or there are relatively few answers.
Several ways exist to refine the search.
Another is to view the full record of selected articles that look particularly promising from the list of citations. A click on the microscope icon brings up the complete computer record. This offers an opportunity to emphasize the importance of understanding the content and organization of a typical record, including the abstract and different types of indexing. This scanning can trigger other ideas for searching, either to focus the search or extend it with additional terms. For the chiral epoxidation search above, a review article shows that manganese catalysts are used, so re-searching the topic by substituting manganese for the general term metal will identify other relevant articles.