You can search 6 publication fields:
This is the default. It will look for all of your keywords in each field.
Example: lead; zinc will only return results with lead AND zinc in the SAME field.
Therefore, for best results, use keywords that are probably in the same field. For example, searching an author name and a commodity will have few results as the two words would rarely be together in the same field. Use the Any of These Terms method for this type of search.
This will search for any of the keywords in all fields; e.g., "lead;zinc" will look for lead OR zinc in each field and return publications with either or both.
This method is also best when the keywords are from different fields, such as title and author; e.g., to find all zinc-related reports by Rice type zinc; rice.