def get_header_item_group(header, group):
    """
    Filter header and return list of items of a specific header
    group (e.g. 'CTYPE').
    Return empty list when unable to find @group in @_header.items().

    Parameters
    ----------
    header: dictonary
        The dictonary that contains the header of the SST cube file.
    group: string
        Keyword you want to find.

    Returns
    -------
    list: list
        List that contains the matched group else it is empty.
    """
    return [i for i in header.items() if not i[0].find(group) and not i[0] == group]