code: public Observable<Void> inquireAsync(String vaultName, String resourceGroupName, String fabricName, String containerName, String filter) {
          return inquireWithServiceResponseAsync(vaultName, resourceGroupName, fabricName, containerName, filter).map(new Func1<ServiceResponse<Void>, Void>() {
              @Override
              public Void call(ServiceResponse<Void> response) {
                  return response.body();
              }
          });
      }
docs: Inquires all the protectable item in the given container that can be protected.
  Inquires all the protectable items that are protectable under the given container.
  
  @param vaultName The name of the recovery services vault.
  @param resourceGroupName The name of the resource group where the recovery services vault is present.
  @param fabricName Fabric Name associated with the container.
  @param containerName Name of the container in which inquiry needs to be triggered.
  @param filter OData filter options.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceResponse} object if successful.