There are basic search strategies that can be used when employing various text based search queries when locating information:
And
Only records with BOTH search terms will be retrieved
The AND operator is the most commonly used operator
Or
Used to search synonymous terms or related concepts
This search will retrieve records where EITHER of the search terms is present, resulting in a larger number of hits
Not
Used to exclude a term or concept from your search
The NOT operator is the least-used operator
Different search tools (e.g., catalogs, databases, web) have different searching rules and features. Consider reading directions and help screens before using a tool that is new to you, or view instructional videos or screencasts when available. Some additional types of databases (especially those emphasizing statistical data) may at times favor arriving at results through building of reports or cross-tabulations. And yet other categories of database sometimes help one arrive at relevant results through the use of selecting preferences from a series of menu options or other related filters. Most of the time, do not settle only for the initial list of results you immediately retrieve from any search query. Instead, make full use of options to filter and/or sort those results to align them as closely as you can with the subject matter desired within that source material, or the content types you prefer (newspapers vs books vs book chapters vs images vs video vs government reports vs scholarly journal articles vs magazine articles vs statistical data, etc) or the time period covered that you are seeking.