def query(entries, keyWord):
    """
    Filters out entries that match the given substring in the DESCRIPTION
    column.

    :param entries: A pandas Dataframe containing transaction entries.
    :param keyWord: The substring that is searched in the description column.
    :return: A pandas Dataframe containing matched transaction entries only.
    """
    return entries[entries["DESCRIPTION"].str.contains(keyWord, na=False)]