FQL location_post, distance (latitude, longitude) returns inconsistent results

I am requesting location_post

as follows:

SELECT id FROM location_post WHERE distance(latitude, longitude, "37....","-122....")<100

      

        
        
        
      

    

In theory, this should return everything location_post

within 100 meters.

By doing this, I got 2 results.

However, when I increased the range to 1000, I got more results, but the previous 2 results are not two of them. Should I get what I got with the lower range when I increase the coverage?

Please tell me if I don't understand something.