Still haven't found what i'm looking for

blogs gurus give some advices about how shold looks like your blog. One of their advices are related to write about one specific topic. I agree, because if you hace readers, they know what are wating for or topic will find in your blog. But, like U2 song, i still haven't found what i'm looking for. I've writting about Oracle, Oracle's Technet, Ubuntu linux (I use it!!), about Project Management (GTD, WBS, etc), personal stuff, my son's birthday... the topics are very differents, and i even like to write about music that i listen, cocteau twins, dead can dance, yes, genesis, Jazz (jean luc ponty, pat metheney, al di meola)... or concerning books i read [Jose Saramago, Julio cortázar ] ...