Advanced search for Training Material does not use keywords correctly?

[joakimlindblad]

Hi, I wanted to find our nice training material about tracking, so I go to Advance search, pick in 1st two boxes: Content Type: Training Material, and Operation: Particle Tracking
https://biii.eu/all-content?type=book&field_has_function_target_id%5B%5D=4141&field_type_target_id=All

and I get zero hits.
However, e.g. https://biii.eu/analysis-microtubule-orientation-tracking-imagej-directionality-analysis-matlab
covers exactly the topic "Particle Tracking" (not the Operation, which is possibly the cause of the problem)

It is not possible to select Topic: Particle Tracking in the advanced search though.