This is a chapter from a book about the way ethnography, a research method,
has developed as part of anthropology, an academic discipline. It is enough for you to skim the text. You don't need to grasp let alone recall all the many details of anthropologists and their work from the twentieth century that it introduces. However, the text gives you a good overview of the process of producing what scholars often think of as 'data', and it may inspire some useful reflections on qualitative methods more generally.
Several copies of the whole book are available at the SKS (Finnish Literature Society) library. https://helka.finna.fi/?lng=en-gb