If my total tax is remitted as withholding tax should I still file income tax return?
Yes you still need to file a return (provided you meed the income threshold and other requirements) even if you don't expect to get a refund back. The reason is that withholdings are just estimates of what you will actually owe in tax, and are rarely completely accurate. Your actual tax is computed by the final return. The return will show if you under-withheld and owe more tax, or over-withheld and get a refund.
Income tax is not like sales tax that is computed on-the-spot. It is based on the entire year's activity. Withholding just looks at your current period's income, extrapolates it out to a year and guesses at what your total tax will be (based on annual income, deduction status, etc.), and then computes the portion of that tax for the current period. It does not know things like whether or not you itemize, are eligible for credits, etc. so it's often imprecise.