How to query Content Property in Technical Documentation

Hi Team,

Could you please explain how we can query 'Content' property in tp_Block itemtype. 

As per my knowledge, all root and node elements along with id's will be wrapped up inside Content property/column in tp_Block table. If I have to find/fetch any id of certain elements like Title/Subtitle/Graphic, is there any way to achieve through Custom code? or should we have to write any SQL query in custom method.

Kindly help.