Dream is a psychological phenomenon, usually an illusion caused by the activity of brain neurons during sleep. Everyone's dreams are different, so we can't judge a person's fate and future according to his dreams.
In addition, being bitten by a snake or being entangled by a snake may be caused by sleeping in an incorrect position or having nightmares, not a symptom.
Therefore, we should treat these statements rationally and don't be overly superstitious.