Hello there. I'm new here, and I just want to know why these fotos were not accepted. Do yo have any ideas?

Adobe is strict in quality of image.

Snapshots taken with your phone camera might be OK for posting on Instagram but that’s not what Stock customers will pay for.  They expect commercial-quality content for use in professional projects like magazines, TV ads and merchandise. 

Read through your Contributor User Guide. Start with the 4-part photo requirements.

1. https://helpx.adobe.com/stock/contributor/submit-your-content/submit-photos/photo-submission-overview.html
2. https://helpx.adobe.com/stock/contributor/submit-your-content/submit-photos/technical-legal-requirements-photo-submission.html
3. https://helpx.adobe.com/stock/contributor/submit-your-content/submit-photos/photo-editing-best-practices.html
4. https://helpx.adobe.com/stock/contributor/submit-your-content/submit-photos/submit-photos.html

Also, this is what you’re competing with in Stock:

• https://stock.adobe.com/search?k=flower  75 million
• https://stock.adobe.com/search?k=coffee+drink  9 million
• https://stock.adobe.com/search?k=cafe+late  25K 

Hope that helps.

Hello,

Composition is very important!

Composition

Adobe Stock is not a social media platform, so please do not simply upload photos just as you shot them.
You need to pay attention to factors such as focus, brightness, color balance, composition, aesthetic appeal, commercial value, and post-processing.
In short, you need to study photography.

Soft focus, composition and in the first one, white balance issues

Also, check your histogram and color cast. This one is overexposed and has a strong yellow color cast. 

Too tightly cropped and they are both out of focus. Compose your assets to give the buyer some breaking room for cropping or to add text.