Sure. Essentially Lutherans have a stricter definition of a Sacrament. A Sacrament is defined as God's word connected to a material element that communicates grace, instituted by Jesus Christ, for the whole Church. As such of the traditional seven which Rome accepts, we see only three can be properly called Sacraments: Baptism, the Lord's Supper, and Absolution. Though whether Absolution is properly a Sacrament or just sacramental, has been sorta fuzzy. So you might find Lutherans count only two Sacraments, and others count three. It really depends on whether one considers the spoken words of the pastor a material element or not.
Marriage, Ordination, Unction, and Confirmation are not regarded as Sacraments because they don't meet the above mentioned criteria. Which doesn't mean that there isn't a sacramental character in these things, lots of things can be sacramental without being Sacraments. In a sense, there's no definitive number of things that can be sacramental in character. But for something to be a Sacrament we believe there needs to be a strong definition of what a Sacrament is, and so we rely on Scripture itself and what Jesus says and has given explicitly for His Church as means of grace--for the forgiveness of our sins. And we consider Augustine's language of the Sacraments as "visible word" (word connected to material element, and thus being "verbum visibilis") to be immensely helpful. As, fundamentally, what makes the Sacraments Sacraments is the word of God. The Gospel itself is here in Baptism, the Lord's Supper, and Absolution, just as it is in the very preaching of the Gospel. Just as the word of God is clearly proclaimed in the Lord's Prayer, in the faithful prayers of the Church, in the faithful hymns the Church sings, in the sermons and homilies, and of course most sublimely Scripture which is the very divinely inspired and written word of God, the manger which holds Christ and lifts up Christ before our eyes in each and every sacred page. Which is why we always speak of Word and Sacrament, not as two things, but as a single thing.
There isn't remission of sins in Baptism because there's water, but because of the word of God, which in Baptism is connected with the water. Which is why St. Peter says in 1 Peter 3:21 that baptism now saves us, but not as the washing of dirt from our skin, but as the pledge of a new conscience before God by the resurrection of Jesus. Of course Baptism involves water, but it is because that water has been united to God's word that it is not just getting wet, it is forgiveness of our sins (Acts of the Apostles 2:38), being crucified, buried, and raised with Jesus Christ (Romans 6:3-4, Colossians 2:12-13), it is being clothed with Jesus Christ (Galatians 3:27), it is new birth from above (John 3:3-5, Titus 3:5), a washing of water with the word (Ephesians 5:26). Without the word of God, it wouldn't be the laver of regeneration, it would just be getting wet.
-CryptoLutheran