yoshimi: command not found

Have You tried accessing the binary with the full path?

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/yoshimi - from package: yoshimi

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