If I typed multiple words into the Quick Search box, I wasn't getting the expected results. When I analysed it, the cases not returned were those where word1 only appeared in the description, and word2 only appeared in a comment. So if I typed foo bar , the expression was text ~ "foo bar", which if you expand text is similar to (description ~ "foo bar" or summary ~ "foo bar" or comment ~ "foo bar" ...) when I was expecting ((description ~ "foo" or summary ~ "foo" or comment ~ "foo" ...) and ( description ~ "bar" or summary ~ "bar" or comment ~ "bar" ...)).
That is to get what I want, I had to type text~ "foo" and text ~ "bar" into the basic search box. Is there a way that typing foo bar into the Quick Search box would expand to text~ "foo" and text ~ "bar" , and not text ~ "foo bar"