ceres-tree-find: 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/ceres-tree-find - from package: python-ceres

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

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