It will be good always to see quick response in the form of answers and comments from the community. But how to know correct or suitable tags to my question for quick and suitable people attraction to my question as those tags play a vital role to reach suitable people to answer my question.
I'm not going to duplicate information here. Similar to Super User Meta, there's a Meta for the whole Stack Exchange engine, called Meta Stack Overflow. You'll want to read this question there:
The gist of it is:
Choose at least one or two good matching tags. Those are the ones that are most frequently used. At the very least, choose windows or linux (etc.) for your operating system, if you're looking for practical solutions to a problem.
Check out the most popular tags, and see if they fit. Popular tags have more followers, thus your question will probably be highlighted for them.
Use broader tags if your question applies to this general tag. You don't necessarily have to tag your question ubuntu if it's about something that is the same in all linux distributions. However if your question only applies to ubuntu, I would add both tags (or just the specific one).
And please remember:
Do not add too many tags. They won't help getting more views, and dilute the scope of these other tags. Especially, do not add unrelated tags.
Do not create new tags unless there's a good reason to.
Do not use meta tags.