Mystique locators issue

require 'selenium-webdriver'
driver = Selenium::WebDriver.for(:firefox)
driver.manage.delete_all_cookies
driver.manage.window.resize_to 1280, 800
driver.navigate.to 'https://www.upwork.com/o/profiles/browse/?q=Ruby%20Selenium'
parsed_data = []
driver.find_elements(:css, '.oDescription.m-md-top.m-0-bottom > em').map { |value| parsed_data << value.text }
puts parsed_data.inspect
driver.quit