def find_records(dataset, search_string):
    """Retrieve records filtered on search string.

    Parameters:
        dataset (list): dataset to be searched
        search_string (str): query string

    Returns:
        list: filtered list of records
    """
    records = [] # empty list (accumulator pattern)
    for record in dataset:
        if search_string.lower() in record.lower(): # case insensitive
            records.append(record) # add to new list

    return records