Hi,
Sorry to hear about Sasha. I am a bit concerned by the fact that there is some blood in her vomit. It is normal for dogs to be sick after eating grass, but not every day and not if there is blood in it. Yellow flem is just bile, a normal constituent of the stomach juices. Ignore the wetness of the nose, that is an old wives tale.
Assuming Sasha hasn't been doing this for longer than a week, then you should starve her for 24 hours and then feed only a bland diet such as chicken and rice, small portions, for 3-4 days. If she seems lethargic or is not drinking and able to hold water down, she must be taken to a vet ASAP.
Good luck
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