Sorry to burst your bubbles, but…
What are browser cookies?
Little files that are generated when you make a search that store bits of info on your computer so to make searching quicker based off previous searches.
Essentially, twitter's search function is taking input from your stored cookies and making relevant search queries quickera and easier to get too.
If you were to clear your browsers cookies it would go back to either no suggestion or whatever is trending at the time.
Open up an incognito tab and try it and it does the same.