I cannot find them on the 1870 census, but I have found the following on the 1860 US census:
1860 Census, St. Louis County, Missouri, 3rd Ward of St. Louis City, 17 July 1860, page 251, beginning line 1:
Henry Luken, age 26, Male, Occupation: Dairyman, Value of Personal estate: $1,000; born Oldenburg
Margret Luken, age 22, Female, born Hanover
Regina Luken, age 2, Female, born Missouri
Busselens (Bersseleus?) Neihaus (Neihans?) age 24, Occupation: Teamster, Born Hanover
Herman Neihaus, age 22, Occupation: Laborer, born Hanover
Theresa Neihaus, age 60, no occupation, born Hanover
Theresa Neihaus, age 18, Servant, born Hanover
In the next household:
Tobias Broms, age 51, Male, Dairyman, Real estate value: $5000; personal estate value: $1500, born Hanover
Theresa Broms, age 43,Female, born Hanover
Maria Broms, age 18, female, born Hanover
Julia Broms, age 11, born Missouri
Henry Bierman, age 28, Male, occupation: Teamster, born Hanover
Bernard Snelt, age 25, Male, Occupation: Teamster, born Hanover
Bernard BremerKamp, age 48, Male, occupation: Teamster, born Hanover
On page 250, beginning line 18 (Could this be the parents of Margaret Luken above?)
Bernard Brinker, age 50, Male, Occupation: Dairyman, Real Estate Value: $5000, Pers est value $1000 born Hanover
Helen Brinker, age 40, Female, born Hanover
Bernard Bierman, age 23, Male, occupation: Teamster, born Prussia
Henry Draga, age 40, Male, Occupation: Teamster, born Brunswick
Henry Selman, age 30, Male, Occupation: Teamster, born Prussia
Havier Frick, age 16, Male, Occupation: Butcher apprentice, born Baden