Hi,
if I serach for (without quotes) "lock pages in memory" the search finds nothing.
But if I only search for "lock pages" I find the pages I was locking for.
It has been my experience that using "common, non-descript words" (e.g. in, the, and, etc.) in a search string often hinders instead of helps. If you have not yet, you might want to take a look at How do I find stuff? for some helpful tips regarding this.