What no "select similar" option? That would be handy.
The Magic Wand tool will select areas of similar color. Is that what you're looking for?
Instantly same color separated all over the same layer without 'collecting them all (Shift)? Thanks
I'm still not 100% following you. Are you trying to select colors similar to a selected one that are next to each other? Or select all instances of the same color (or similar ones) within a layer whether or not they're touching?
Yes, I select a color with magic wand. Then how to "Select Similar" (colors) on same layer?
Yes, whether or not they are touching
Have you tried going to the menus to Select > Color Select. Once the color select window is open, you can use the dropper tool from the window to select a single color from your image then refine the color to include a wider range of that hue, a range of saturation, and a range of value. You can see what is being selected in the preview window. I think this may be what you are looking for. Enjoy.