I updated an old post of my blog and changed the title and some other things; 3 or 4 days ago. Today, when I saw that post on Google with old title, I felt that something is going wrong by me. I want you to ask that why did the old title appear in Google instead of New. Do I need to make some changes on Google Webmaster Tools or resubmit sitemap after updating the posts or a post? I’m waiting anxiously for your satisfying answer.
@saadwasil You don’t need to change anything on Google Webmaster Tools . It will take some time to change the old post Title on Google Search Engine .
Internal Linking Is Important : Internal Linking is important , Google Spider Crawler could’t access your old URL without linking to your OLD Post’s from the new Blog-Posts that your made in Blogger . By making Internal Links from new Blog Post’s that you are made in Blogger , Google Crawler can easily access to the old URL and changes will easily made up on Google Search Engines .
As @MUHSIN_MOHAMED_PC Said, You need to update some internal link in Updated post & some fresh text, so Google Crawler automatically update your post in Google Webmaster Tools.
Sitemaps are resubmitted only when you have done a major clean up on your site like deleting dozens of old posts, changing the URL structure, Redirected Domain to a new domain and also when you have edited the Titles in large numbers.
There is never harm in resubmitting sitemaps but don’t do that frequently. Only do that when you have made some major changes to your posts content.
Google re-crawls pages after a fixed time and once it finds a change made to Title, Description, or the inner content, it will auto update the indexed data and display the new results on Search Results Pages. It takes around a week for Google to update its cache so you wont see immediate changes.
You can surely update old content and it wont surely harm your SEO but do not change the permalinks ever and nor change the Title content completely, making slight changes to titles is permitted but do not stuff new keywords inside titles just for the sake of ranking for new LSI keywords.
You can correct Spell mistakes in titles and rearrange the words combination but do not try to add new keywords in titles.