It gives 500 results to me too (havent seen them all)but if you look more close at the results you will notice that for example with the word PAWN you get results from the ut2004 forum and a few other places but NOT from the udk threads.If you type ¨¨pawn¨¨ again in the search bar and choose search in UDK only option you will get 0 results.Try it
For the ¨¨pawn¨¨ example word i expect to see a flooded udk topics result as it was more used and not sections from old ut2004.