Although it seems like book-length ethnographies should contain the word "ethnography" in the title or description, they frequently don't. There are, however, some strategies that you might find helpful when searching.
Strategies for Finding Ethnographies
Search "ethnography" and the culture you are interested in, as keywords:
(ethnograph* OR ethnolog*) pueblo
Search the subject heading "social life and customs" and the culture you are interested in, either as subject heading or keyword.
"social life and customs" navajo
"social life and customs" igbo
Search the subject heading "social conditions" and the culture you are interested in, either as subject heading or keyword.
"social conditions" maori
"social conditions" tutsi
Add specific characteristics to any of the strategies noted above.
"social life and customs" navajo family
"social life and customs" igbo religio*
Or add specific date ranges (Note: these are publication dates of the books not the time period when the culture was studied).
"social conditions" maori 1860..1950
"social life and customs" navajo family 1951..2013