The file name gives only 1SS348, a part number in the Japanese 1SS small-signal diode series, common in Toshiba catalogues. The PDF is 68.5 KB and filed under schematics, though at this size it is almost certainly a datasheet for one component. A repair technician would consult it for the pin assignment, internal configuration, maximum reverse voltage and forward current before replacing a damaged diode. Verify the package type and laser-marked code on the PCB part, since several 1SS devices share similar tiny SMD cases.
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.