Hi @Singh, Gurprateek Welcome to Microsoft Q&A forum and thanks for reaching out here.
I agree that the button images are all same and a bit confusing, I will share this feedback with respective product team to see if they can improve the UI experience for find and replace feature.
But in the meantime, you can hover over on each of the buttons to see what they are intended for (Please see below gif for what I mean). Or you can use those shortcuts as need.
Appreciate much for sharing your feedback regarding this functionality.
Hope this helps.
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