I just configured a custom Google Search Engine for OSLC specs: https://cse.google.com/cse?cx=007668210173932793183:pvsycrapeug. Please give it a try, it should search inside most of the spec locations:
https://github.com/oslc-op/oslc-specs/*https://docs.oasis-open.org/oslc-core/*https://docs.oasis-open.org/oslc-domains/*https://archive.open-services.net/wiki/*https://archive.open-services.net/bin/view/Main/*
There is also a new specs page with multiple revisions of most common OSLC specs: https://open-services.net/specifications/
An example of a search:
