vfnmz: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/vfnmz - from package: namazu2-index-tools

You may install the required package with command apt-get install {package}

Error in other languages:
vfnmz: bevel nie gevind nie
vfnmz: comandă negăsită
vfnmz: comando não encontrado
vfnmz: commande introuvable
vfnmz: command not found
vfnmz: käsku ei ole
vfnmz: không tìm thấy lệnh
vfnmz: komanda nerasta
vfnmz: Kommando nicht gefunden.
vfnmz: kommandot finns inte
vfnmz: komut yok
vfnmz: nie znaleziono polecenia
vfnmz: níor aimsíodh an t-ordú
vfnmz: no se encontró la orden
vfnmz: no s'ha trobat l'ordre
vfnmz: opdracht niet gevonden
vfnmz: parancs nem található
vfnmz: perintah tidak ditemukan
vfnmz: príkaz nenájdený
vfnmz: příkaz nenalezen
vfnmz: команда не найдена
vfnmz: командата не е открита
vfnmz: 命令找不到
vfnmz: コマンドが見つかりません