tyls: 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/tyls - from package: terminology

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

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