One successful way to search American Life Histories is using occupations and names of places people have worked.
You have seen an example that was found using the search term "circus."
Experiment with some of the following terms or use your own:
cowboy blacksmith laundress longshoreman pirate
robber butcher teacher midwife undertaker
waiter fisherman dancer astronomer surveyor
writer seamstress bricklayer slave handyman
servant pianist

Another area to look for is places people work.
Experiment with some  of the following terms or use your own:
 
sawmill (or saw mill) textile mill ranch packinghouse mine
railroad plantation grocery army night club

Write five terms here you might search with: