In what situations should I "select a field" to search in SLUth Search Plus?
The "Select a Field" drop-down menus next to the search boxes in SLUth Search Plus should only be used when you'd like to perform something other than a keyword search. For example, if you know the title of a specific article you'd like to find, you could do a "Title" search for the article. Another option would be to search for articles written by a specific author using the "Author" search (last name, first name).
Most of the time though, you'll be searching for articles on a topic. In that case, you'll want to stick with the default search and not "Select a Field" in SLUth. This allows you to search every part of an item's record (title, author, publication, abstract, full text, etc.) for the keywords you type in.