I am always looking for new positive things in life

Someone who has just tiled a bathroom floor cannot walk into anyone else's bathroom again without checking the grout. The eye gets trained, and then it won't stop.

Looking for good things works the same way, with one difference: the brain arrives pre-trained to scan for threat instead, because for a long stretch of history that was the more useful setting. Noticing the pleasant thing is the newer skill, so it takes deliberate repetition.

Which is why the practice is worth more than the mood it produces. On a bad day the looking still works even when the finding is thin — a decent orange, someone letting you out at a junction.