Schmidt has cards in 1975, 1978 and 1980 - 1983.
I don't know how he didn't get a card in 1976 and 1977 since he led the league in homers from 1974 - 1976. Maybe it is because he also led the league in strikeouts?
His 1979 omission isn't a surprise. His 1978 season was probably his weakest one. That was the only year in a twelve-year period where he didn't get any MVP votes.
He came back to lead the league in homers in 1980, 1981, 1983, 1984 and 1986. He led the league in RBIs four times and walks four times.
He was MVP in 1980 and 1981 so I guess I could see why people were chasing his cards.