Is anyone able to tell me what these are? The openings are tapered as though whatever is placed in them is meant to be easy to remove.  They don't look like the shape of anything I can think of, especially the semi-circles.  I don't think they are pastry cutters, they are too thick and would be made of metal, plus...the shapes.  I doubt they are molds, they wouldn't have an open bottom.   
Oh...wait...I should have thought of a reverse image search. It seems they are dumpling molds.  https://rotanya.com/product/magic-dumpling-model/ 