The Query Builder allows you to search for specific reference fields to include in your search, with specific search terms within that field. The fields are joined together using Boolean operators (OR and AND). This is a simpler option to use if you do not have a detailed knowledge of writing search queries.
If you prefer to write out your own custom search string, you can turn off the Query Builder and input your search directly in the text field. The search syntax used in CuratorCR is similar to what would be used in a PubMed search, for example.