There’s a way for improve dynamic shadows quality?
I have raytraced shadows but all the ways looks no quality.
I put some pics: Screenshot by Lightshot Screenshot by Lightshot
Thanks 
Try increasing you distance field resolution scale for each object.
To add to Roel’s post and to trouble-shoot a little further.
We can trouble shoot this a little easier by viewing the “Mesh Distance Fields” in the view port. This method will allow us to see the meshes distance field representation and how much to increase the distance field resolution by.
You can enable this view by going to the viewport > Top left select “Show” > Visualize > select Mesh Distance Fields.
The default DF resolution is set to 1 but may need to be increased slightly to somewhere between 2-4. I’ve not had to personally set anything higher than that, but the option is there if it is needed.
Here is an example:
Distance Fields representation using the Show > Visualize > Mesh Distance Fields
This is the shadow result:
If you look at the mesh on the left it has a lower resolution than the mesh on the right. Distance Fields will generate a simple mesh that captures the shape of your mesh to generate the shadows. By increasing the resolution you can get better shadows, but this will be more cost intensive the higher the resolution, so only increase as needed.
Also, to make sure you are fully testing and using only Ray Traced Distance fields in your light source make sure that you set the cascaded shadow distance from 20000 to 0. This way you can see the distance fields only.
It’s possible to use both these in conjunction to get some better results and specific uses cases, but for the purposes of nailing down the issues here with Distance Fields it’s best to turn it off for the moment.
I hope this has helped and if you have any questions feel free to ask.
Tim