Can anyone help me to indentify the technical issue of my photo?

You may not understand: you need to upload the full resolution pictures here to the forum so that we can look at them and help you to identify the problems.

What I can say is that your framing is bad:

• Plate: hand, cut off at the lower border.
• Flowers: cut off at the lower border.
• Tube: cut off at the right lower border, perspective, kind of something to the right. 

The flowers look even as a miniature picture out of focus.

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

you must supply full sized images.

these are originally taken by me nikon 7500d cam

As you probably know, many technical issues are only visible at 100% -200% of the original image, and all images need to be carefully checked at this magicification. We can't give much useful advice from thumbnails, except for a some elements you will have already considered like composition and histograms.