How to make products visible in one collection only?

[Orcust]

So I’m doing a special promo where I want to email a segment of customers a link to a collection, so sort of a “secret link” for lack of a better term.

i want the products of this collection to only be accessible via the link sent and not accessible by searching anywhere.

the only issue that I’m having is the items will still show up in the “all” collection. Is there any way to make it so these items only appear on the collection that I link and nowhere else on the site?

please do not suggest apps as I am not currently willing to pay for any. 

[NomtechSolution]

In your Shopify admin, go to the "Collections" section and select the "Special Promo Collection." Under the collection conditions, choose "Manually select products" and remove any default conditions that may be present