opensearch-discover: 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/opensearch-discover - from package: surfraw-extra

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

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