I’m not sure I understand what it is you want to do. Can you describe it in a bit more detail?
Current date time +/- days will never return an empty result, so it’s a bit hard to say what you want to achieve with it.
If you want to Do A Search For:count the listings in a specific, the easiest way might be to create a data point in each Listing with the month (1, 2, etc) and year (2017) so that you can filter easily by month=1 and year=2017 for example.
You could achieve this by creating a Month thing in your database, manually add months for foreseeable future and then use workflows to firstly determine which month you are in, and then to update a ‘Total’ field within that Thing. I have done this before and it’s less clunky than it sounds… but it’s weak point is that the ‘rolled up’ values will not refresh if you make any changes to the database. And so it’s quite easy for the numbers to go out of sync.
I have just published a chart plugin that can achieve what you are trying to do natively. The last example in the library here sounds similar to what you are looking to do. You run a search for all of the Things that you are looking to ‘rollup’ and it takes care of the rest.