searchd: 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/sbin/searchd - from package: dpsearch
/usr/bin/searchd - from package: sphinx

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

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