Saudi Arabia is fighting terrorism in ways that count, but don't get much noticed outside Saudi Arabia. The most recent move was to reduce the powers of the religious police. These guardians of public morality can still arrest you, but they can no longer interrogate and prosecute you. They have to turn those they arrest over to the regular police (who don't get on very well with the religious police, so you can see where this is going). The religious police are not a uniquely Saudi institution, several other Moslem nations have them (although only Iran has a force that is nearly as obnoxious as their Saudi brethren.) In Saudi Arabia, the religious police are considered a bunch of losers, who get off by abusing people for real, or imagined, immoral (in a strict Islamic sense) behavior.
The religious police are one of several examples of Saudi culture that have contributed to the creation, and growth of Islamic terrorist groups in the kingdom (of Saudi Arabia). The Saudi government is trying to rein in these horrors it has unleashed, and curbing the religious police is one way to do it. There are more difficult problems to fix. The most serious one goes back to the 1970s, when the government agreed to let the religious establishment run the educational system. This was part of a deal that got most of the clergy on the government's side, for even back then, there were plenty of armed, angry and violent religious fanatics in Saudi Arabia. Indeed, Saudi Arabia has long been the home of religious maniacs, and the Saudi kingdom was established only with lots of help from Islamic radicals. But the Saud family found that it was constantly at odds with the religious fanatics, who also had lots of popular support.
Since September 11, 2001, the Saudis could no longer deny that they had allowed the creation of a culture of intolerance and hate that churns out more and more Islamic terrorists. The 2003 invasion of Iraq really enraged Islamic radicals in Saudi Arabia, and caused them to make war inside the kingdom. That increased the growing dislike for Islamic radicalism by Saudis. But it will take over a generation to turn off the hate machine. The Islamic conservatives control of the education system means that several generations of kids have been indoctrinated to be religious bigots, and to approve of religious violence (at least as long as it is Moslems who are being violent.) Getting control of education from the Islamic conservatives is one of those vicious battles fought in the shadows. Curbing the religious police and replacing textbooks is how the war is fought.
Oddly, by Western standards, the government, and most Saudis, are not terribly upset at situation. That's largely because of another quirk of Islamic culture, the belief that everything that happens is "God's will." This attitude leads to a widespread lack of personal responsibility, and the failure of the Arab world in particular, and the Islamic world in general, to keep up with the West in terms of economic and social progress. But when the Islamic terrorists you created start setting off bombs in your own neighborhood, "God's will" becomes a challenge, not an excuse.