gnuchess: 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/gnuchess - from package: gnuchess

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

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