dochelp: 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/dochelp - from package: dochelp

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

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