gobject-query: 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 CentOS possible default full paths are:

/usr/bin/gobject-query - from package: glib2-devel

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/gobject-query - from package: libglib2.0-dev

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

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