How to not scroll synchronously?

[Pierre-de-la-Verre]

I have file A with "big data-sections" X, Y, Z and file B with similar sections, but in order Z, Y, X.
X from A is on the top, X from B is on the bottom and they are not displayed side by side.

On the left side I see the string "hello how are you" and now I want to ..

• search for "hello how are you" on the right side
• but the left side should not scroll; it should stay at is current line and
• I can compare the context of "hello how are you" on the left and on the right, but on completely different places of the files.

I'm sure there is an option for it, but I can not find it .. ;-)