Hi,
I have a problem with rendering a section made in Sketchup. Even though on Sketchup’s scene there is no wall (because I cut it with section tool), when I render in VRay both the wall and other cut objects are still visible. I would be grateful for the help how to overcome this issue 
Hi @izabela_pycio ,
Welcome to Chaos Forum.
Please show some examples of your renders to better understand your issue.
What is your V-Ray version? You can check it here: Extensions > V-Ray > Help > About and please share a screenshot with us.
Please create a new ticket via this form where you can upload your scene for us to review. To do this use the Pack Project tool (Extensions > V-Ray > Pack Project tool) to archive your scene with all the assets. Additionally please share your SketchUp version.