thesaurus2any: 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/thesaurus2any - from package: libbiblio-thesaurus-perl

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

Error in other languages:
thesaurus2any: bevel nie gevind nie
thesaurus2any: comandă negăsită
thesaurus2any: comando não encontrado
thesaurus2any: commande introuvable
thesaurus2any: command not found
thesaurus2any: käsku ei ole
thesaurus2any: không tìm thấy lệnh
thesaurus2any: komanda nerasta
thesaurus2any: Kommando nicht gefunden.
thesaurus2any: kommandot finns inte
thesaurus2any: komut yok
thesaurus2any: nie znaleziono polecenia
thesaurus2any: níor aimsíodh an t-ordú
thesaurus2any: no se encontró la orden
thesaurus2any: no s'ha trobat l'ordre
thesaurus2any: opdracht niet gevonden
thesaurus2any: parancs nem található
thesaurus2any: perintah tidak ditemukan
thesaurus2any: príkaz nenájdený
thesaurus2any: příkaz nenalezen
thesaurus2any: команда не найдена
thesaurus2any: командата не е открита
thesaurus2any: 命令找不到
thesaurus2any: コマンドが見つかりません