<…> Someone will write article with his own experience but another person will say it is not true.. That means you are calling him a lier..
Not necessarily at all. People can have different ideas, perspectives or knowledge on a matter, and therefore express their counter opinion. In general terms, that is something that should be appreciated, as it’s not infrequent for people to write things that are wrong or misleading, often unintentionally. As a reader, it’s better to view contrasted information than to take for granted everything we read, though over time, you may tend to take a closer shine to some specific people’s comment/views.
And those people that condemn work are getting more merits than the OP himself from his own experience.
That could be due to multiple factors, one of which is the chances that the rebuttal bears some clear-cut arguments that make the counterview seem valid, or more reasonable than the view it counters.
<…> I don't know how to quote individual line of an article here in this forum. What should I do. Teach me.
Once you quote, edit the text within the quote freely to leave the pertinent parts, as I’ve done above.