When you are posting a blog on your blogspot, blogger automatically uses your title to create a url for your post. This happens only if you have enabled post pages in the Settings » Archives » Enable post pages setting to true. However if you are using a fairly long title, blogger will simply truncate at the end of the last complete word so that the total remains within 40 characters.
Most blogspot/blogger users don't realize this but this is what blogspot does behind your back. There is no option to edit the url during posting or editing. However there is a way in which you can get back the control over the process and prevent blogger from truncating your SEO optimized URL to mere jargon.
The URL for a blogspot post is created the first time a post is saved. So create a SEO targeted title when you post your blog entry. Then go back and edit your entry and change the title to whatever way you wanted it to be. This way you will end up having a good URL as well as having all your keywords in the content of the URL Text.
This small mistake that most bloggers make could cost the bloggers several ranking points in the different search engines. "Tutorial on how to make beautiful pie" would bring you a totally different audience from "Tutorial to how to make beautiful pie-charts". So next time you post your blog entry double check your URL and make sure that it conveys what it was intended to convey and that it contains all the relevant keywords that you wanted it to contain.