dfutool: 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 CentOS possible default full paths are:

/usr/bin/dfutool - from package: bluez

You may install the required package with command yum install {package}

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