All information about publications in library catalogs and databases is stored in records. Each record has separate fields for title, author, keywords, year of publication, etc. You can search each field separately. The fields are therefore called search entries.
Usually you type your search in the first search bar you come across (simple search or basic search). You search all the fields at once. In full-text files, such as Nexis Uni, you even search the entire text of the document.
This can be useful, but often produces many irrelevant hits. It is better to choose a specific search entry. In databases and catalogs, an advanced or multifield search usually includes a search form where you can easily choose your search entry.
Example Sociological Abstracts
Suppose you are looking for publications on the well-known anthropologist Malinowski:
Which is the best option always depends on your research question. In this case, the title search will probably yield the most relevant results, followed by the summary search.
With subject-specific databases, it may be worthwhile to see if there are additional search inputs relevant to your research