Asrock Extreme Tuning Utility: CPU Multi?

These forums are not the most helpful place as AsRock rely on a couple of volunteer mods to run everything.
Welcome to some of the worst motherboard tech support on the planet - not the worst motherboards to be clear.

If you expect an answer you should think about what someone who can be bothered replying to you would want to know.
What actual board model you have would be a good place to start.
What CPU cooling do you have?
What Power Supply do you have.
Even with an active forum community (Gigabyte, Asus, MSI) you will be asked for this kind of info if you want help.

That being said, seems the FX-8350 will go to 4.7Ghz all cores, but unless you have a good board with solid VRM's and good VRM cooling most don't recommend messing with LLC (load line calibration - essentially how your board uses voltage from your PSU to compensate for fluctuations that can keep a safe and reliable daily overclock) on the board.
Find a way to get a fan to blow on these, a 40mm fan on top blowing down would be an easy solution.

Since your first approach was to use an OC utility, I'm guessing overclocking is something you are fairly new to, generally a much more stable OC is done through understanding the BIOS features.
Some boards have limited BIOS options, so you may have to resort to utilities - "AMD OverDrive" seems popular if your BIOS isn't useful for OC features.

Attaching a few resources for you to start your 'journey'.
But if you are serious about dialling in a solid OC, you will do much better to Google than come to these forums.
AsRock either don't have the resources to utilize in their community, or it's simply not something they care too much about, both very odd outcomes for a company that actually does make good boards with quality components for the most part.

Good forum, where this user ranks boards that he would bother trying to OC your CPU.
AsRock Fatal1ty 990FX is the only AsRock board recommended in this forum:
https://www.overclockers.com/forums/showthread.php/728209-FX-8350-Asrock-970-Extreme4-Not-a-good-couple?p=7427437&viewfull=1#post7427437

Jayz2Cents Video Guide on Overclocking your CPU:
https://youtu.be/MckeAmnDeTk

Random Youtube vids - NOTE that these may be using different motherboards, so you need to understand that different boards have different names/meanings for overclocking features - AsRock's LLC (Load Line :
https://youtu.be/CJuTTq4sO3o

https://youtu.be/y03kvuSewqk

AMD Overdrive on Gigabyte GA-970 board:
https://www.techpowerup.com/forums/threads/overclocking-a-new-fx-8350.234492/

Good luck, and stay safe - little steps, then test stability using something like 'RealBench' from Asus as a very good entire system benchmark that much more accurately reflects real world usage for gaming etc.