def METHOD_NAME(file_path, time_a, time_b, match_string):
    """Searches a string in a log file for all the lines where date is between time_a and time_b
    :param logs_dir: path of the directory where log file is located
    :param time_a: time which defines the starting point of the time frame
    :param time_b: time which defines the ending point of the time frame
    :param match_string: string to be search in any log lines
    :returns: If the string is found it returns True. False is returned otherwise
    """
    with FileReadBackwards(file_path, encoding="utf-8") as frb:
        for line in frb:
            match = re.match(HEALTHCHECK_LOGREGEXP, line)
            if not match:
                continue
            columns = line.split(' ')
            str_date = columns[0] + ' ' + columns[1]
            dt_line = datetime.strptime(str_date, HEALTHCHECK_DATEFORMAT)
            if dt_line < time_a or dt_line > time_b:
                break
            if line.find(match_string) > 0:
                return True
    return False