In most of the data at Familysearch, first name only searches are not possible. This is okay for ancestors named John or William, but sometimes some of us have unusual first names that are passed down in specific families or first names that are kind of unusual and last names that can be written incorrectly.
I am searching for Elam Blain(e) in Ohio--searching the Ohio tax records on FamilySearch. I thought perhaps Blain was totally mispelled and tried searching for men with the first name Elam. There were a few, none of whom had a last name close to Blain.
I like being able to search based on first names only. This is a nice improvement.