images rejected due to technical problems

The first picture isn't that bad and could pass with a few adjustments: sharpening and small exposure adjustments, as there is a part of the blacks missing in the histogram.

The problem with the roses pictures is that they are out of focus.

What you need to know with flower pictures is, that there are abundantly many flower pictures, so they are vetted very stringent, and absolutely no error is allowed. So, even if they were technically correct, all the pictures would get refused, with may be the exception to the first one because they are simply missing the "wow"-factor.

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

All of the photos have background noise and should be sharpended.

Photo 1 is overexposed so that details in the petals are lost. It should be cropped and you should use a smaller aperture next time.

Photo 2 the rose in the upper left and the fence should be cropped out. 

Photo 3 the main rose is cut off.

Photo 4 too many distractions. For example the bamboo. 

Here an example:

can someone help me? I'm new and don't know what I'm wrong