Today, my advanced search showed six hits for messages to me in the last two days, whereas the real number should be thirty to fifty. The posts listed were also the oldest from that time frame. Is there a known issue with the search?

Not seeing other reports so far. There was a server reboot yesterday which may have impacted this. 

let us know if the problem continues with new posts ...

Will keep you updated.

For the days since the search works but I still do not get results for the day when the incident happened.

Today I get one search result for messages to me in the past week where I received somewhere between twenty and fifty.

Are you using Search to me or the discussion dropdown where you see only new messages you haven't looked at?

search to me

Not a fix, but try using to: younggandalf instead of to: me . Does that work any better for you?

Both show four messages for the past month where there should be hundreds.

Sorry there is no obvious answer and still not seeing similar reports so far. Where is this happening.