0. Wrap the text by tr or QObject::tr.
1. Generate the ts file,
2. Translate almost every words of the ts file(some of them are left empty).
3. Run lrelease to generate qm file
4. Load the qm file as following

QTranslator custom_translator_;
qDebug()<<__func__<<a.applicationDirPath();
if(custom_translator_.load("english_to_turkish.qm", a.applicationDirPath())){
    qDebug()<<__func__<<"can load english to turkish";
    if(a.installTranslator(&custom_translator_)){
        qDebug()<<__func__<<"can install translator";
    }else{
        qDebug()<<__func__<<"cannot install translator";
    }
}else{
    qDebug()<<__func__<<"cannot load english to turkish";
}

The return values tell me qm file can be loaded and installed, but none of the text are translated to Turkish, every words remain as English. Any possible wrong I commit? Thanks