Well, that's a good question @anasustic. Are you using Sling Models with ModelExporters? If yes, your models may also be implementing ComponentExporter.getExporterType(), in this case, you can call resource.exporterType() which returns the component resourceType. If you're not using ModelExporters, ...

Is this what you looking for?    Return as generic resources  List<Resource> resourceList = new ArrayList<>(); for (Resource resource : resource.getChildren()) { if (resource.isResourceType("resourceType1") || resource.isResourceType("resourceType2")) { resourceList.add(resource); } ...

Your question is missing details on what is not working.On which version of SDK? latest version? Do you see any errors in the browser console or error.log? Which RTE plugins are not working?