Some issues with search

Hi
I have been trying out search and am having some issues
1. When I search for a word, even if all the categories are disabled (filters and categories) , the page is still brought up. Needless to say, the page is also brought up with everything enabled
2. When NOTHING is checked, it seems everything is brought up.
3. Additionally, even when the term is NOT in the title, and I turn on “search by title”, the page with the searched term is still brought up. This happens even when nothing else is checked. Or when the relevant category is checked.
4. Finally, sometimes when there is no result, it goes to a new page(see the snip attached).
And sometimes, it says “No results” on the same page at the right hand side (when there are results, these always show at the right hand side)

The URL for the search is given below, with username and password. Your help is appreciated in resolving these issues.
https://akhundforbes.com/search-test/