No, you literally didn't.
I'm asking why Luffy can literally draw blood by simply grabbing Kizaru, but when he attacks, he can't, so he has to be not damaged.
What you're literally saying can be true in 2 scenarios.
1. Luffy wasnt serious when he attacked with Cymbal (which is weird to think of)
2: Simple Grab > Cymbal (given cymbal is crushing but has much more power than Grab, this is idiotic to think too)
Option 3: You're leaving out the context that Kizaru was grabbed off-guard when Luffy grabbed and squeezed him and thus had no time to prepare himself for the incoming attack whereas he could see Dawn cymbal coming.
The fact that Kizaru hasn't further spat out any blood shows how he was tough enough to take the attack. There is no logical reason why the attack should do no damage to Kizaru unless it's too weak to do so.
We literally see Kizaru huffing on the ship, that's either due to the attack putting his body under immense stress and pressure or because he killed VP (he was shown breathing heavy after stabbing him).
Blood does not equal damage (which is always the case because not every single attack draws blood)
Blood does not equal damage
depending on the type of attack used.
A slash needs to draw blood or it has done no damage. Being crushed leads to bleeding out of your mouth as proven when Luffy squeezed Kizaru.
What damage has dawn cymbal done to Kizaru, can I ask that ?