Perform search query nepomuk

I'm playing around with those search queries in Dolphin (timeline:/...) I want to add a this week search, but I don't know what the keyword is to use. By default it came with Last Month, This Month, Yesterday and Today. I tried ThisWeek, but it did not work. Yet if I just use "timeline:/" on its own, I get a list of folders I can drill into.

I've also found out I can use the keyword 'tag' to look for, well tags.

Is there any documentation showing me what other keywords I can use?