Hello,
As you've guessed, one needs to be very careful about changing rules.
And: the same rules apply to all languages queried, not only the one(s) you would like to see more hits for.
Some engines, including Bing, allow for a 1-year filter, which is applied.
There were 0 hits certainly for that reason; on Jan 1st there were 63, now 38.
Actually, if you click on the Oberon / Bing cell with the hit number, you get the exact query.
Cheers
Gautier