can not get my individuals from my ontology using search method in owlready python

I have an ontology : https://raw.githubusercontent.com/amiraelsayed/lumiere/master/lumiere3.owl I want to get all lessons for specific class called CS-Java I have tried to use owlready search method and add to it filtration with lesson name and object properties but always give 0 while it should retrieve about 19 item This is my individual this is the class and it is contain list of lesson individuals onto.search(part_of=”*”) it brings all lessons in all courses and when I used onto.search(part_of=”CS-Java”) it return 0 while I need it to return only lessons in this course Answer I guess your search returns 0 result because the