testsolv: 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/testsolv - from package: libsolv-tools

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

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