Javascript magic is used on this page. You need to make POST request manually. Here is POST request (from Firefox's HTTPFox extension): 
termYear    2014
term    10
course_number   
multiCourse 
course_title    
instructor  
subject AAS
course_start_eval   -
course_start_time   -
course_end_eval -
course_end_time -
course_status   -
course_level    -
course_units    -
virtual -
termCode    201410
runMe   1
clearMe 1
reorder 
gettingResults  0
search  Search
_cf_nodebug true
_cf
_nocache true

[download]
And here is the code: 
$mech->post("https://registrar.ucdavis.edu/courses/search/course_searc
+h_results_mod8.cfm", 
    Content => {

        termYear => "2014",
        term => "10",
        ...
        subject => "AAS",
        ...
    },
);

[download]

In reply to Re: WWW::Mechanize Webcrawler by Anonymous Monk
in thread WWW::Mechanize Webcrawler by Thoery55

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.