Search Corrupt

help me please!

Details – are you using a search plugin?
Got a link?

Yes I use a search plugin and it section is ok
but main wordpress search is corrupt

exsample for search word “eolico” on *molisenews.net*

https://www.molisenews.net/index.php (link page of search)
https://www.molisenews.net/page/2/ (link for previous news)

instead of this:
https://www.molisenews.net/?s=eolico (link page of search)
https://www.molisenews.net/?s=eolico&paged=2 (link for previous news)

moreover the search term is stopped until date 17 april 2007 omitting all the others posts publishes