X-ray diffraction (XRD) signals are determined by the crystal structure of the single crystal or powder you are working with.  Which are you doing?  I'm guessing that you're doing powder diffraction.  You should be seeing a plot of brightness (of xray scattering intensities) vs. distance from a central spot (the image of the unscattered xray beam).  The positions and brightnesses you see are rather complicated to interpret.  You can't just say that a certain spot corresponds to a specified atom, so you can't use XRD to identify the elements present in your sample.  I believe there are reference patterns published by professionals whose work is preparing pure samples of crystal compounds, crushing and grinding them and measuring the diffraction pattern they produce.  Your best bet would be to locate such a database and learn how to match its patterns with your samples.  Its a fingerprinting type of process, in other words.

First off, those are not spectra. Better call them XRD traces or patterns that have peaks.

Then, it would be helpful to know what material you are examining. Without that I will be making wild guesses. Maybe you can post an example of an XRD trace?  But I will post some suggestions from my specialty area.

This website is a good start to understand the basics of clay mineral ID using XRD but also provides good information on XRD in general.

https://pubs.usgs.gov/of/2001/of01-041/

I also recommend "Moore & Reynolds 1997 X-ray diffraction and the identification of and analysis of clay minerals". This book basicly explains everything you need and also discusses non-clay minerals.