It is hard for you to share a lot of detail in a tweet so let me just make up ONE example and answer your question. I open GA's keyword report. I see this:

KW: "Avinash is a awesome" Visits: 2 

KW: "Avinash is not awesome" Visits: 0

There are two reasons this could happen.

Paid Search. For AdWords accounts that are linked to Google Analytics in very RARE cases it happens that "CLICK" data is available from AdWords for certain keywords but there is no Visit data available in Google Analytics. Perhaps because the tracking code did not fire off or, more likely, there was no tracking code on the landing page. Then you'll see some zeros in the visits column. One way to verify is to click on Traffic Sources > Campaigns > Clicks tab to see the non-zero impressions from AdWords.

Organic Search. Let's use this example.. You come to the blog on the search phrase "Avinash is awesome," you land on a irrelevant page on this blog, you hit the back button and go back to Bing, you try a different search phrase "Avinash is not awesome," you land on the right page, you love it, you read lots of post, you leave. So how does GA decide which keyword to assign that visit to? Should each keyword show one Visit? That would not be right. Should it be the first search phrase you came on? The second one? 

GA will show you both, but put a zero for the second. Essentially it is assigning "CREDIT" (attributing) the visit to the first keyword ("Avinash is awesome"), and a zero in Visit for the second keyword ("Avinash is not awesome"). But each keyword gets "credit" for other METRICS. So if you had seen three pages on the keyword "Avinash is awesome" then it will show one visit but it will show three page views. And if you came back again, in less than 29 mins on the keyword "Avinash is not awesome" and saw ten pages and converted then that kw will show zero visit, 10 pages and one conversion.

IMPORTANT: This type of behavior is rare so you should not see 0 visits often.

It is hard for you to share a lot of detail in a tweet so let me just make up one example and answer your question. I open GA's keyword report. I see this:

KW: "Avinash is a awesome" Visits: 2 

KW: "Avinash is not awesome" Visits: 0

There are two reasons this could happen.

Paid Search. For AdWords accounts that are linked to Google Analytics in very rare cases it happens that "click" data is available from AdWords for certain keywords but there is no Visit data available in Google Analytics. Perhaps because the tracking code did not fire off or, more likely, there was no tracking code on the landing page. Then you'll see some zeros in the visits column. One way to verify is to click on Traffic Sources > Campaigns > Clicks tab to see the non-zero impressions from AdWords.

Organic Search. Let's use this example.. You come to the blog on the search phrase "Avinash is awesome," you land on a irrelevant page on this blog, you hit the back button and go back to Bing, you try a different search phrase "Avinash is not awesome," you land on the right page, you love it, you read lots of post, you leave. So how does GA decide which keyword to assign that visit to? Should each keyword show one Visit? That would not be right. Should it be the first search phrase you came on? The second one? 

GA will show you both, but put a zero for the second. Essentially it is assigning "credit" (attributing) the visit to the first keyword ("Avinash is awesome"), and a zero in Visit for the second keyword ("Avinash is not awesome"). But each keyword gets "credit" for other metrics. So if you had seen three pages on the keyword "Avinash is awesome" then it will show one visit but it will show three page views. And if you came back again, in less than 29 mins on the keyword "Avinash is not awesome" and saw ten pages and converted then that kw will show zero visit, 10 pages and one conversion.

IMPORTANT: This type of behavior is rare so you should not see 0 visits often.