If the left overs aren't attractive to her try heating the left overs from the can for 20 seconds in the microwave. Make sure you stir the food before placing it down. The food should not be hot, just slightly warm. This will cause the food to have more of an odor that she can smell more easily.
Some cats have difficulty eating directly from a can since it is hard for them to get the food adhering to the bottom or the edges of the can. And unlike dogs, cats tongues are not as long and flexible, so they have more difficulty getting into nooks and crannies.
Cat's should eat mostly, or only wet, or canned food. It is better for their urinary health and kidneys, so I would not worry about her not getting adequate nutrition from eliminating the dry food. She may have given up the dry food due to decreased sense of smell, or because she may have dental disease, or even more likely, she may have a bit of arthritis in her jaw and finds chewing hard food a bit painful, since she has to use her jaw more to chew the dry food.
Thanks a loooot for your fast reply! It meant a lot to me 'cause I'm very worried about my sweet "Coco" not eating properly.
This morning I tried your advice and it worked. Me myself could smell the food when I removed it from the microwave, something that doesn't happen when I take it out of the fridge, so it seems she also noticed it.
I don't feed her right from the can but in a plastic feeder, I was afraid she could get hurt 'cause the edges of the cans are sharp, but the reason you gave me makes a lot of sense too.
About the "dry or wet" matter, it's hard 'cause some doctors say dry food helps them to have their teeth clean and that they need to make some effort to chew 'cause that's what wild animals do. But I feel comfortable with what makes Coco comfortable. She's old now and I want her to feel good, that's it. I don't overfeed her, she's weighting 9 pounds or so, she still plays like a kitten catching paper balls in the air, so....
I've always heard about the kidney problems so feeding her with wet food makes me feel better.
Thanks again for your kind help and advices.
Have a great Sunday!
Ellan