How soon do you see results with a yoga workout?

People expect all sorts of things from hatha yoga, which I suppose is because there are plenty of modern fad yoga-like things that promise them.
Hatha yoga is about preparing the body to be relaxed and energized for meditation without discomfort/distraction or fatigue.

Try some knockoff like Pilates if you want to work on your ‘core’.
It’s not yoga but Pilates’ similarity to yoga could accidentally get you some deeper yoga-style benefits.
Or just try some of the usual abs exercises like crunches and leg-lifts.

There’s nothing wrong with regular hard-core exercise when that’s what you need.
Then come back to your hatha yoga to calm your mind.

With the amount of yoga questions you’ve asked in the last few days (almost 10 by my count), I’d think a yoga and/or fitness forum would get you better results from those who are more familiar with the subject. Some jellies do yoga, but you’d find a lot more people on a forum geared toward that.

Here’s one.
Here’s another one.