If you want to know that, Read Google websearch parameters and The Ultimate Guide to the Google Search Parameters. The google search query structure is broken down into chunks and has detailed information about their purpose.
You will get to know what for the parameters in your search queries are. If you understand the purpose of each parameters, then it is as easy as the back of your hand to get the answer of your question.
The following are some of the decoding of Google's search query syntax.
Basic Search URL:
Advanced Search URI
as_q=test (query string)
&num=10 (number of results [10,20,30,50,100])
&as_epq= (complete phrase)
&as_oq= (at least one)
&lr= (language results. [lang_countrycode])
&as_ft=i (filetype include or exclude. [i,e])
&as_filetype= (filetype extension)
&as_qdr=all (date [all,M3,m6,y])
&as_nlo= (number range, low)
&as_nhi= (number range, high)
&as_occt=any (terms occur [any,title,body,url,links])
&as_dt=i (restrict by domain [i,e])
&as_sitesearch= (restrict by [site])
&as_rights= (usage rights [cc_publicdomain,cc_attribute,cc_sharealike,cc_noncommercial,cc_nonderived]
&safe=images (safesearch [safe=on,images=off])
&as_rq= (similar pages)
&as_lq= (pages that link)
&gl=us (2-digit country code in lowercase)
There are still a lot more available since there is various types of search queries are there such ad image search, etc., Please go through the links i have suggested above and also i have some new resource for you that has a detailed information.
Thanks to @Polynomial for pointing out to summarize the contents from the links.