I was able to fing just about all the Steve Miller tunes I was lookig for by trying a couple of searches....try various album names or song titles.
I rarely find everything on the first search...
The songs may also have multiple listings on various compilation albums.
I downloaded just about all of Number 5 (inc. Good Morning)...as well as Children of the Future and Sailor.
Some tracks blend into others so you may need to get the next track to sound decent w/o an abrupt ending...