STAMFORD - Stamford detectives are asking for the public to help find the van they say could contain vital information about three recent shootings that claimed two lives.Officers say a witness saw several people on Spruce Street fire multiple shots out of the back of a white delivery van on Wednesday morning. Authorities believe the van also contains information about a murder on Custer Street and a 21-year-old who was found dead Wednesday in Norwalk. Stamford detectives say the two murder victims were friends and the white van could fill in the missing information. They ask anyone with information about that van to call the detective bureau.