Samsung SM-G355H document in PDF format, 3.21 MB, the model code for the Galaxy Core 2; the HrM suffix likely points to a hardware repair manual section, though that reading is uncertain. Samsung repair documents of this type typically include block diagrams, schematics, component layouts and fault-finding procedures. Technicians use them to trace battery and charging lines, locate key ICs and find test points. Open with any PDF reader and confirm the board revision before relying on part positions.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @tamirat_moobile. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.