Hi I am new in mobile repairing and learning ,I have seen most samsung service manual they contain a section "Main Electrical Part List" but I can't find any value for the component,like some chip resistor and capacitors are unmarked ,how to find their values...

And also on web I could'nt find any full Samsung Schematic Diagrams only Service Manuals are avaliable,am I missing something?

I am asking for general ... for all samsung phones...how you experts find it?

Thanks for any tips and answers