mais Animal in Harvest Moon: A Wonderful life?

You can't do anything to get them. I don't know what anyone told you but it seems there is no way to get any animal other than farm animais (like chickens and cows), a dog, cat, and a horse. If you befriend Lumina's grandmother, you can get one of her gatos eventually; and at some point Takakura will bring you a horse. Other than that there are no other animals.

For instance, the little animal sometimes near the dig site with a bandanna around its neck. You can't keep it, I'm pretty sure. I've tried so many ways. I can keep checking though.

Edit: Okay, I found a really trustable site/person (link) and you'll see it says you will never recieve that chihuahua (the bandanna animal). And it doesn't talk about the others. I assume they'd know if it was true. You'll just have to assume that you can't get any other animals.