man1p: 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/share/man/bin/man1p - from package: filesystem

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

Error in other languages:
man1p: bevel nie gevind nie
man1p: comandă negăsită
man1p: comando não encontrado
man1p: commande introuvable
man1p: command not found
man1p: käsku ei ole
man1p: không tìm thấy lệnh
man1p: komanda nerasta
man1p: Kommando nicht gefunden.
man1p: kommandot finns inte
man1p: komut yok
man1p: nie znaleziono polecenia
man1p: níor aimsíodh an t-ordú
man1p: no se encontró la orden
man1p: no s'ha trobat l'ordre
man1p: opdracht niet gevonden
man1p: parancs nem található
man1p: perintah tidak ditemukan
man1p: príkaz nenájdený
man1p: příkaz nenalezen
man1p: команда не найдена
man1p: командата не е открита
man1p: 命令找不到
man1p: コマンドが見つかりません