lshw: 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/lshw - from package: lshw

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

On Debian possible default full paths are:

/usr/bin/lshw - from package: lshw

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

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