I've been converted to using wildcards on just about every name I can, on every site I can, in every search box when I can. It does not always work, but sometimes it does.
My aunt Emma Sargent is occasionally listed in various records as Emma, Emmar, or Emmer. I started searching for her as Emm* whenever a site allowed the use of the wildcard operator.
My own ancestor Ira Sargent is listed in one record as Iran. Do not ask me why, but he is. Even on his first name I have started using wildcard searches.
If you are looking for a John, consider searching for Joh*.
If you are stuck on a name and a wildcard search won't increase your hits to the point you cannot view them, consider reformulating your search using wildcards---even when you don't think you really have to. You just never know what you may find.