search history - more questions

[SHANKAR R-R66203]

I found out that
   :his /
Gives the listing of the search history.

In a particular file, I tried using
:his /

      #  search history
      4  \<wallace_tree_4_w4\>
      5  ^I
      6  crg_arm
      7   
      8  ipss
     10  #
     11  perl D:/Profiles/r66203/utils/v2html/vhier_ls.pl -f
verilog.harlech > test.hier
     13  \<usb_rcv\>
     14
\(^\s*\(\<else\>\)[EMAIL PROTECTED](\#\s*(\s*\w\+\s*)\s\+\)\=\w\+\_s*(\(\/\/\
)\=\)|\(^\s*\w\+\s\+#\s*(.\{-},\)
     15
\(\(^\s*\(\<else\>\)[EMAIL PROTECTED](\#\s*(\s*\w\+\s*)\s\+\)\=\w\+\_s*(\(\/\
/\)\=\)|\\)
     16
\(\(^\s*\(\<else\>\)[EMAIL PROTECTED](\#\s*(\s*\w\+\s*)\s\+\)\=\w\+\_s*(\(\/\
/\)\=\)|\(^\s*\w\+\s\+#\s*(.\{-},\)\)
     17
\(\(^\s*\(\<else\>\)[EMAIL PROTECTED](\#\s*(\s*\w\+\s*)\s\+\)\=\w\+\_s*(\(\/\
/\)\=\)\\|\(^\s*\w\+\s\+#\s*(.\{-},\)\)
     20  \<reg_out25\>
     87  \<rd_even_flash_enb\>
    138  pllmrbi_ipi
    155  ^\s*pllmrbi_ipi\>
    156
\(^\s*\(\<else\>\)[EMAIL PROTECTED](\#\s*(\s*\w\+\s*)\s\+\)\=\w\+\_s*(\(\/\/\
)\=\)
    162  \(^\s*\w\+\s\+#\s*(.\{-},\)
    177  \<ipp_obe_txdata_b\>
>   192
\(\(^\s*\(\<else\>\)[EMAIL PROTECTED](\#\s*(\s*\w\+\s*)\s\+\)\=\w\+\_s*(\(\/\
/\)\=\)\|\(^\s*\w\+\s\+#\s*(.\{-},\)\)

I do not understand why the numbers are not consecutive.
How the search history can be deleted ??


And finaly another question -

How do I put the result of the following command in a variable.
    :his / -2 

Regards,
Shankar