"Seek and do not find" is the absolute rule of the ego's way of perceiving.
It's very simple logic.
1) You already have everything you need. You are love.
2) Deny everything you are. "It's not in you".
3) Feel deprived and lacking and driven to search for what you lost anywhere, except in you - because as per step 2, it is clearly not in you (notice here that we never mentioned it being anywhere ELSE either though).
4) Now you go on a passionate hunt for what you lost - yourself - God - everywhere OTHER THAN where it is. Everywhere separate from you. In every illusion that prevents you from being as you are.
5) COMPLETELY fail to find it, because it is NOT OUT THERE.
Sometimes you'll find something which you think is your salvation - idols, objects, people, relationships, activities, places, etc. You invest them with 'hope' that they will be 'the one' that will save you from this dilemma of denial of yourself. BUT at the same time, you absolutely DO NOT believe that they will do so, because you're convinced the truth is NOT in you and never will be ever again.
So whatever you find starts to fail and reveal its cracks and show evidence that it is not working - it's not restoring you to happiness or love or who you are. So you become disillusioned, maybe angry that you've been led astray. You feel deceived and abandoned and frustrated. This REINFORCES your feeling that you are not loveable, that you are not good enough for God, that you are not with God, and that you are not yourself. You feel terrible. Even worse than before. And how does the ego suggest you solve this?
"Why not go looking somewhere else, since it's obviously not here?" - ... in other words, MORE DENIAL, leading to more compulsion to seek outside yourself where you WILL NOT find what you're looking for.
Every effort you make to 'hold on', forces you to 'lose'. Every effort to 'have' or 'get' forces you to lose. Every effort to 'gain' what you lost reinfoces it's loss and loses even more. Every time you try to 'keep' what you 'little left' you fear to lose, you believe in its loss even more and it goes away. Every time you try to control what's happening so that you don't lose any more of what you value, it all gets taken away from you.
This is how the ego functions. It is insane. Only the insane would tell you to go looking for what you don't have because of how you failed to find it the last time you went looking. The last hunt didn't work? Keep on looking, you're sure to find it someday! Not.
What you're really looking for is God. What you're looking for is your True Self. It's not fancy cars and people and sex and bodies and tv shows and weddings and vacations and rainbows and pets and political rallies and movies and whatever else. It's not out there.
What you want is BEHIND the wall of denial that you've constructed, which you USED the ego to accomplish - or rather, you made the ego BY denying who you are and what you already have.
Everything you really want and CAN ever really HAVE and BE and EXPERIENCE, is already given to you by God. It is what you are. It is love Itself. With this there is nothing else that you really want. That is why the course says, "this world holds nothing that you want". Sobering. It holds nothing you want because it's not WHAT you want, what you want was already yours - it's YOU, as God created you. And you already ARE that. It's in you.
And let's be very very clear about something, because this is the ego's entire cover-story that we're about to blow. Ready? .... Denial is NOT removal. Denial does NOT destroy. Denial does not get rid of anything. Denial merely COVERS UP what is already there and PRETENDS that it is not there.
You want to know what the ego's crowning glory of denial is? The total denial that you are love, that you even live? It's DEATH. Death is DENIAL, it does NOT remove anything, it does not destroy anything, it merely PRETENDS that Life (God, You) do not exist.
It's a cover up!
You merely need to look with Holy Spirit at where you are DENYING - God - Your True Self - and uncover that, expose it to the light again, and reclaim your "natural inheritance". God's already given you everything you could possible want to be satisfied. You're just choosing not to want it. And because of that, you WILL NOT find anything better or more satisfying anywhere else.
Undo denial and you awaken to the love that is already your natural birthright. God created you AS love and that will never change, NO matter how much you might DENY it. And it is still the truth about you, because denial has not touched it or changed it. You are love.
Love is the truth, forever.