Adjusting number of measures in each line

I'm trying to get 2 and a quarter pages down to just 2 pages and I want first to be able to control the number of measures in a line (and then the number of staves on a page). I tried shift/bracket with the selected measures in the screenshot, but the first click just compressed measure 38 a little and subsequent clicks did nothing (but they were stored somewhere because they were recognized by command Z undo). It's very easy to decrease the number of measures in a line by inserting a line break. Surely there must be some way to increase the number of measures too?