jaaa: 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/jaaa - from package: jaaa

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

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