I want to know if Na2B4O7 exists on this xrd data. I ran the program to check the peaks, but I don't know how to interpret them, so I leave this question.
I strongly recommend performing a proper Rietveld refinement or related procedures to check whether certain phases are really present. Taking the level of complexity in your data and the candidate structures, I really doubt that you can make definite predictions from "search match" procedures. "Search match" procedures should be taken as inspiration but not more. I have seen too many inappropriate evaluations on the basis such procedures such that I propose to exclude evaluations based on simple search-match procedures from serious scientific papers.
The attached diffraction pattern matches PDF 01-076-0756 well. Pawle's fitting based on the data from this PDF card also gives a decent result. So it is mainly NaB(OH)4(H2O)2, not borax.