Wikipedia defines confirmation bias this way:
Confirmation bias is the tendency to search for, interpret, favor, and recall information in a way that confirms or supports one’s prior beliefs or values. People tend to unconsciously select information that supports their views but ignore non-supportive or contradicting information. People also tend to interpret ambiguous evidence as supporting their existing position. The effect is strongest for desired outcomes, for emotionally charged issues, and for deeply entrenched beliefs.
Confirmation bias is part of what makes biases so sticky. Intentionally or not, we tend to seek out information that supports our views and that further solidifies our views and beliefs. And technology isn’t much help; we now know that social media algorithms are designed to show us information in our newsfeed that supports and strengthens our existing views which validates our biases.