You can combine any or all of the above search techniques to further refine your search. For example:
"chang* mail-tool" finds documents containing literal phrases such as "change mailtool," "change mail tool," "change mail tool," "change mail-tool," "changing mailtool," "changing mail tool," "changing mail-tool," and so on.
"display button" viewer searches for "display button" and "viewer" in proximity to each other.