The 69.8 KB PDF here is labelled with nothing more than 1SS321, a part number in the Japanese small-signal diode designation used largely by Toshiba. No laptop model or board number is given, so treat it as a component datasheet filed under schematics. During board repair it helps identify a diode by its SMD marking, confirm which pad is the cathode, and compare ratings with possible substitutes. Check package size and marking carefully, because several closely numbered 1SS parts look identical on the PCB.
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 @cyberlanelectonik. 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.