wfst_run: 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/wfst_run - from package: speech-tools

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

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