@coolsista-paris Grapeseed oil is a lighter oil so that's interesting. My hair doesn't care for olive or coconut oils as sealants. My sealing oil mix has a base of castor oil (2 oz). Then I add one ounce of avocado oil. Finally, I dilute that with my lighter oils apricot, sesame, and jojoba. I've been using safflower oil in my mix instead of jojoba with no ill effects. The castor oil as my base gives it some weight but don't use it straight because it's sticky. I can't think of a better term for that feel. You can try a mix like that. Since it's cold outside, I wouldn't try a light oil like grapeseed alone. If were warmer, I would experiment.
But if you have a serum that you know works, check out the ingredients and compare it to your stash. You may be able to create something similar when you run out of the product you like. Or find you can stretch that product so that it lasts longer with something you made. Wild growth hair oil was the first that I liked. I tried to mix something similar but use up all the oils that I purchased over a year ago.
Did you use a styler under the grapeseed oil?