I am trying to find out why google is saying "Submitted URL seems to be a Soft 404" for site search page, it appears if someone searches for somthing and the search result is empty then google does not like it, is there any way to solve this problem

As per https://support.google.com/webmasters/answer/181708?hl=en it seems like Google does not like the page having next to no content but returning a 200 status code.

Just make sure that the search page displays more content if no results were found.