The most significant leakage on our 40 Ocean was from the stanchion feet, including into the electronics locker, which happens to have one of those feet. You can remove a small panel at the back and top of the lockers all around the furniture to (just about) access the nut for the stanchion feet, then pull them out and rebed with an elastic sealant. Make sure you scrape out any old grot and clean up well.
The other one was from the deck/hull joint, but that was leaking less. Depending on which year your 38 Ocean is (the older ones had the rubbing strake lower on the topsides), the joint is accessible behind the teak rubbing strake, which is easy to remove once you take the stainless strip off it. Then it's a matter of raking out the insufficient sealant, again cleaning and degreasing and installing new, of which you need a lot.
But do the stanchion feet first, they're more likely to be the issue.