Quick answer
Wisdom is close enough to see. The fool is scanning the horizon for it and missing what is in front of him.
Read both lines
The contrast is spatial and slightly comic. One man has wisdom in view, right there; the other is looking at the ends of the earth, which is exactly where it is not. What the image diagnoses is a real habit, the assumption that the answer must be elsewhere, exotic, or not yet available. This book keeps insisting the opposite, that wisdom is shouting at the city gate and available to anyone paying attention, and the fool's problem here is not lack of access but a gaze aimed past everything useful.
Related: Proverbs 8:1–3 · Proverbs 14:6 · Proverbs 2:1–5
New King James Version®, Copyright © 1982, Thomas Nelson. All rights reserved. Full copyright information. Scripture provided by API.Bible.
Go Deeper
If this verse has been used to put weight on you that it was never carrying, ask about it directly.