commands and packages

["enediel gonzalez" <enediel@hotmail.com>]

Hello

I  need to install a sofware who requires the following commands to work 
properly, the installation detects that they aren't installed yet.

ypcat rusers ypwhich xhost

?How could I know the package's name who contains a specific command?
I have at this moment sarge stable


Thanks in advance for any answer

Enediel

Linux user 398956