Your system may work differently, but my experience with the search box in the upper right of the Documentation page is that it only works when I hit "Enter" on my keyboard. Clicking on the magnifying glass icon doesn't work on my system. YMMV.
Don Mason
Studiocat i7 4790, 16GB RAM, 500GB SSD Program, 1 TB HD Samples, 2 TB HD Audio, HD 4600 video RME Ladyface (Pepto-Bismol pink version of Babyface - used and ugly, so it was cheap)Win 10 x 64 bit, ProAudio 8, 9, Sonar 1.0... long unmusical hiatus... Sonar Professional, Sonar Platinum Lifetime BFD3, Native Instruments Komplete 10, Waves Gold Bundle