vhdl_count: 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/vhdl_count - from package: sloccount

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

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