When searching a database there are terms that can be used to achieve broader results or less but very specific results. Below are different search terms and how they will effect the results.
The words AND/OR/NOT (sometimes called Boolean) can be used to group sets of search terms together in a meaningful way; which will improve the quality of your search results because you are customizing the results to suit your specific needs/topic.
Use AND to reduce the number of items found by letting the database "know" that these two concepts (safety and water) must be together. For example: this search on water AND safety in ArticlesPlus finds fewer items than either water or safety alone. Plus, the true context of your topic is not represented.
Use OR to combine synonymous or alternate terms and increase the number of results. For example: the search water AND safety AND (Ohio OR West Virginia) in ArticlesPlus finds less items than before, but more than searching either water AND safety AND Ohio or water AND safety AND West Virginia.
Use NOT to exclude a specific concept from your results. For example: this search on water AND safety AND (Ohio OR West Virginia) NOT lead in ArticlesPlus finds less items because it is excluding any results with the word "lead". In other words, I want materials about water safety in two states that are not about lead.
As you are completing your "PreSearch" you should be collecting and writing down keywords, terms or phrases that describe different aspects of your topic. When you begin searching within a database as part of your research, having this list will be very useful.
When searching a database you cannot enter a sentence into the search box and expect to get a good list of results. You should use the advanced search feature, then separate out all of your different concepts into separate boxes, keeping AND between each box. You can then enter synonyms for your different concepts into one box and link them together with OR.
In the example below, the first box contains multiple synonyms for drone and including them will increase your search results. Also, notice on the left side of the page you can limit the number of results by date which will come in handy when you look for newspaper articles written at the time your technology was introduced to the world.
NOTE: Many databases, including ArticlesPlus, have thesauri that will suggest additional keywords or synonyms when you type your search terms in the search box.