I never go pass page 2 of serp in web search neither when checking keyword rank or common query. But in image search I can go up to page 5-10.
One thing I find that total page results rather strange like example search below:
a.) kw1 kw2 kw3 -- total page result more than 100 millions.
b.) kw1 kw2 -- total page result around 30 millions.
Don't b.) supposed to give more result then a.) ?