when i use link target _blank then onClick new tab open and suddenly tab again close

when i use link target _blank then onClick new tab open and suddenly tab
again close

I search too much on Google but i couldn't find any result so i'm posting
my question here
I'm using wordpress 3.6 and the wp e-commere plugin
i'm use this anchor tag
<a target="_blank" href="http://www.google.com">google</a>
i also use window.open(url,'_blank'); // function do same problem
when a user clicks on the link, a new tab opens and within 1 second it
closes again.. its not working in mozilla and chrome, but it is working in
IE
i checked and there is no theme problem.
if i add an anchor tag from e-commerce product then the tag target=_blank
will not work, and if i add a anchor tag from wp product then the anchor
tag will work...
How can i solve this problem?
and if i add href value with out http:// e.g
<a href="www.google.com" target="_blank">google</a>
it opens in new tab successfully
but then its url is
localhost/wordpress/product/www.google.com
if i write a proper href with http://, so there is open and close issue.
Any one know it solution ?
i apply many type of jquery and javascript code, but actually when i write
_blank, and then new tab opening then issue comes