Hi!
1. The front-page search is set to look within many post types, within over 40 000 posts and contents. That is a very big amount of data, and the database cannot handle that easily.
I did the following steps to optimize it:
– Generated and enabled the index table engine
– Only enabled the keywords for titles and custom keywords, as there are already 650 000 keywords from these fields, which is enough. With the content and excerpt this would be over 10 million, which is too much in my opinion.
Now the search should be almost instant.
2. Using the individual priority options you can do it: Individual Priorities
Look for that post, and set the priority to 101. In that case it will always be displayed as first, if matched.