Hi wim, yup like Finema writes above you can use boolean Intersection (the icon says Isect) to do that.

To use it, select one of the pieces, then run Construct > Boolean > Isect, located here:



Then at the prompt that says "Select second object set", select the other object and right-click or push "Done" to finish selecting. That will then keep the portion contained inside of the 2D profile and throw out the exterior like this:




In this particular case it doesn't really matter but the booleans are kind of oriented around working with solids and not so much with open surfaces, because they figure out which pieces to keep and which to throw away based on which volume they are contained inside of. When there are no solid volumes that becomes ambiguous. In this case it's ok because your 2D profile curve is closed and so forms its own solid volume definition. But in other cases if the boolean does not behave the way you are expecting you may need to solidify the object first before doing the boolean, in this case that would mean selecting it and running Construct > Planar to seal off the ends.

- Michael