debiandoc2dbk: 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/debiandoc2dbk - from package: debiandoc-sgml

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

Error in other languages:
debiandoc2dbk: bevel nie gevind nie
debiandoc2dbk: comandă negăsită
debiandoc2dbk: comando não encontrado
debiandoc2dbk: commande introuvable
debiandoc2dbk: command not found
debiandoc2dbk: käsku ei ole
debiandoc2dbk: không tìm thấy lệnh
debiandoc2dbk: komanda nerasta
debiandoc2dbk: Kommando nicht gefunden.
debiandoc2dbk: kommandot finns inte
debiandoc2dbk: komut yok
debiandoc2dbk: nie znaleziono polecenia
debiandoc2dbk: níor aimsíodh an t-ordú
debiandoc2dbk: no se encontró la orden
debiandoc2dbk: no s'ha trobat l'ordre
debiandoc2dbk: opdracht niet gevonden
debiandoc2dbk: parancs nem található
debiandoc2dbk: perintah tidak ditemukan
debiandoc2dbk: príkaz nenájdený
debiandoc2dbk: příkaz nenalezen
debiandoc2dbk: команда не найдена
debiandoc2dbk: командата не е открита
debiandoc2dbk: 命令找不到
debiandoc2dbk: コマンドが見つかりません