HowTo find Subitem in QAbstractItemModel and QTreeView class?

Here is the solution:

QModelIndexList Items = model->match(
            model->index(0, 0),
            Qt::DisplayRole,
            QVariant::fromValue(item),
            2, // look *
            Qt::MatchRecursive); // look *

• * Without that argument match() function searches only 1 level