sphinxtrain: command not found

Have You tried accessing the binary with the full path?

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/sphinxtrain - from package: sphinxtrain

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