Why can’t I run a topic search on “worship”?

When using Logos on my iPad, I open Topic Guide and try to search for worship. Typically you get a list of suggestions that you have to pick from in order for it to fill with resources. The suggested list for “worship” is blank. Therefore, I can’t search it. You can’t tell me that this isn’t a Biblical topic that can be explored.

Is this a glitch? What is the deal?