Far too many examiners equate a high level of "keyword hits" with "anticipation" or "obviousness," with no evidence they understand what they are talking about. Just string some keywords together, and hey presto! It's obvious!
My apologies for being so blunt, but this is a real problem. The Office should be embarrassed by the quality of many office actions.
The "keyword hit" attitude of many examiners is often impervious...