For example, if you were interested in knowing whether or not the MSU Libraries owns any books written by Craig Gunn you could do an Author Search, click on the down arrow next to All Fields and choose Author, then enter his name in the search box as Gunn, Craig
If you knew the title of the book you were looking for you could do a Title Search by clicking on the down arrow next to All Fields and choose Title then enter the title in the search box. For example: Standard Handbook of Engineering Calculations
Each title in the catalog is assigned at least one subject heading based on it's content. These headings can be used to find more items on the same topic. It is not always obvious what subject heading(s) will be assigned to particular title. It is often useful first do a All Fields search to find books on a your topic and then look at the subject heading(s) assigned to the useful book titles and then use them to do a Subject Search by clicking on the down arrow next to Catalog and choosing Subject to find more books on the same topic. For example the subject heading for the book Standard Handbook of Engineering Calculations is Engineering mathematics--Handbooks, manuals, etc. You could use this subject heading to find more books on engineering mathematics.