How I can filtering news between 2 dates ? (e.g : From 8-May-2017 to 8-July-2017)
currently this is not possible.
Is it possible to filter dates?
For example, all feeds older than X days put in the trash?
unfortunately filtering by dates is currently not possible.
To define the news that have to be automatically deleted by QuiteRSS go to
Tools -> Options -> Feeds -> Clean-Up
and enable f. e. the option
"Maximum age of news in days to keep".