I also have had very little success with SearXNG when I tried it. The results were limited and success was dependent on which instance you were on. I had better results using my usual web based. There were a few instances that were far better than other instances and supplied successful results. A lot of odd and weird results on certain instances that had the vibe of being a front for something else. I eventually stopped using it altogether after determining that to me it was worse.
It's said a lot that if your need is dire, Kagi is worth the money. My need has not ever been that dire.