tbgrep: 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 CentOS possible default full paths are:

/usr/bin/tbgrep - from package: python-tbgrep

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