numericValues("a123 : 0 abc:123 123:abc xyz:1") // List(123, 1)

def numericValues(text: String): List[Int] = {
  val regex = """([a-z]+)s*:s*(d+)""".r
  regex.findAllIn(s).flatMap(s => PartialFunction.condOpt(s) { case regex(_, num) => num })
}