whichman binary package in Ubuntu Bionic s390x

 whichman uses a fault tolerant approximate matching algorithm to search
 for man-pages that match approximately the specified name.
 The fault tolerant matching is very useful in cases where you remember only
 roughly the name of a command.
 .
    Example: whichman netwhat
    This finds netstat.8: /usr/share/man/man8/netstat.8
 .
 ftff searches the directory tree. This is a case in-sensitive and fault
 tolerant way of 'find . -name xxxx -print'.
 .
 ftwhich finds files which are in one of the directories in your PATH
 and uses a fault tolerant search algorithm.

Source package