tpm_nvread: 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/sbin/tpm_nvread - from package: tpm-tools

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