Trust in the Lord with all your heart, and lean not on your own understanding; In all your ways acknowledge him, and He shall direct your paths.
Do you remember when you were a child trying to learn how to ride your bike for the first few times? Your mom or your dad would stand behind you and hold your bike steady. You would get your balance and slowly start peddling while your parent ran along behind encouraging you to keep peddling! Hold on tight! You’re doing Great! Then their voice would start to seem more faint and you would look back and see that they had let you go on your own, and that last wave and encouragement to look forward and keep going straight!
I hope this symbolism paints a picture in your mind of how God operates. When you first get filled with the Holy Spirit you hear His directions so clear and His voice is right there. Then as you learn how to walk in his steps the voice becomes softer because Now God is trusting you to walk in His paths. Our understanding would have God telling us everything, but He tells us not to lean on our understanding but His.