Great Hunter,  Archie

This is a short story about my cousin's dog, Archie. I don't know what breed he is, (he's breed?) but he looks like a hunting dog.
We found Archie last year at the bus station.He looked awful,dirty and hungry, so (.) we took him to our home. He has (a) very kind eyes,a fine dog.He likes to chase after (run the) pigeons.
Once he was bitten by a snake(,) and we had to take him to the vet. We were lucky that the snake was not poisonous.

A nice story and smart dog. You have several sentences which can be easily combined to make the article read a little smoother. Your writing is good, but it not a bad idea to vary the length of sentences, so as to maintain the reader's attention. For instance, your second and third sentences naturally fit together. Please bear in mind 'I don't know.......' is a statement not a question. Had you written 'do you know.....?' you can then add the question mark. At the end of each sentence please remember to leave a space before the next sentence.