Schematic PDF for the Lenovo IdeaPad S770-14, LCFC board NM-E301, from the FVT build stage as noted in the name. LCFC, Lenovo's in-house manufacturer, numbers its boards NM-xxxx. A technician uses the schematic to follow the power sequence, check rail voltages, identify the controllers involved and read component values. Open it with any PDF reader. Since FVT is an early validation stage, some values or parts may have changed in production boards, so compare against the actual PCB before replacing parts.
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 @cynetitsolution. 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.