When I try to search for terms with spaces, such as "lord of the rings", it returns all of my posts. However, if I just type "lord", it returns results.
Any ideas what would be causing this?
Chances are it's searching using the 'OR' operand, which for will pull up everything that has those common words - 'of the'. There are a number of alternate search plugins for Wordpress - we've had great results (pun intended) using Relevanssi.