wks2raw: 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/wks2raw - from package: libwps-tools

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

Error in other languages:
wks2raw: bevel nie gevind nie
wks2raw: comandă negăsită
wks2raw: comando não encontrado
wks2raw: commande introuvable
wks2raw: command not found
wks2raw: käsku ei ole
wks2raw: không tìm thấy lệnh
wks2raw: komanda nerasta
wks2raw: Kommando nicht gefunden.
wks2raw: kommandot finns inte
wks2raw: komut yok
wks2raw: nie znaleziono polecenia
wks2raw: níor aimsíodh an t-ordú
wks2raw: no se encontró la orden
wks2raw: no s'ha trobat l'ordre
wks2raw: opdracht niet gevonden
wks2raw: parancs nem található
wks2raw: perintah tidak ditemukan
wks2raw: príkaz nenájdený
wks2raw: příkaz nenalezen
wks2raw: команда не найдена
wks2raw: командата не е открита
wks2raw: 命令找不到
wks2raw: コマンドが見つかりません