limit vs. refine

[Barker, Evelyn G]

Hello,
 
Is there a generally accepted usage for "limit" vs. "refine" when talking about a search? In other words, is there something that spells out when in an interface you use "limit a search" vs. "refine a search"? Do they mean or imply different functionality, and is this spelled out in a style book or other authoritative place?
 
I checked the techwr-l site for this and my MS Manual of Style but didn't see anything to answer this. 

Thanks for your help.

 
Evelyn Barker
University of Texas at Arlington