We might missunderstand each other. What I udnerstand is, that you want the search on each (or some) of your sites, but every one of them should only show the results from the site that they are placed on.
Lets say you have 3 sites named: 1, 2, 3. If you want a search on site 1, you need to log in to the site 1 administrator panel and select blog 1 for that search. Then log in to site 2, then select blog 2 for that search, etc… The search field on site 1 will only search site 1 then, the search field on site 2 will only search site 2 then..
In other words, each site must have an own search instance configured.
This sounds like a lot of work I know, but there is no other way to create one engine for all the sites (the reasons are mainly security issues).
I know it's written on the admin panel, that if no sites are selected, then the current one will be used, but in some rare cases it's not working for some reason, and I could't figure out it yet why, and the current blog must be selected.Best,
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