qmlimportscanner: 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/qmlimportscanner - from package: qt5-qtdeclarative-devel
/usr/lib64/qt5/bin/qmlimportscanner - from package: qt5-qtdeclarative-devel
/usr/lib/qt5/bin/qmlimportscanner - from package: qt5-qtdeclarative-devel

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

On Debian possible default full paths are:

/usr/bin/qmlimportscanner - from package: qtchooser
/usr/lib/x86_64-linux-gnu/qt5/bin/qmlimportscanner - from package: qtdeclarative5-dev-tools

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

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