Why Do Some Of My Articles Rank, With Wp TAGS?

[chickblogger]

Hi, guys:

I have a quick question on Wordpress and Google. I sometimes rank but not the normal (usual) way. I rank based on a TAG from Wordpress. lol.

How and why does this tend to happen? Is it because I don't use an SEO plugin, such as All In ONE or Platinum.

[chickblogger]

Do let me know some feedback on this, as its ever loving puzzling me. Thx!