My all photo get rejected without giving any reason.Why ??

You got a reason with your rejections, so no need to ask Adobe. It would be nice to communicate us the reason. (see below for refusal reasons).

What I can say, the first picture is overexposed. You may get inspired by my parameters.

The clouds image is noisy, out of focus and has a white balance problem. Noise and white balance may be addressed, out of focus maces the picture unusable.

If you are new to stock, you should consider these resources: https://helpx.adobe.com/stock/contributor/tutorials.html
Please read the contributor user manual for more information on Adobe stock contributions: https://helpx.adobe.com/stock/contributor/user-guide.html
See here for rejection reasons: https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
and especially quality and technical issues: https://helpx.adobe.com/stock/contributor/help/quality-and-technical-issues.html

The first pohoto has ar tifacts around the flower. View at 300% and you can see this.

Adobe always give a rejection reasons (like "model release needed", "artefacts" or "technical issues"). Please tell us what they said, so we don't waste your time with guesses.