For sure, I do not like the Vault search. It does seem to be poorly designed. I found the Condor docs from the recent archive dump at intel.gov. I dunno if I would have found it if not for the recent release.
Also, I wouldn't doubt it if this was done intentionally if they indeed wanted to make it difficult to find more significant documents. I completely agree, the 'popular' section is full of celebrity names and reports and does not highlight anything particularly interesting.