hey yall. didnt really know where ask this and i could not find the information online/in the wikis (maybe im dumb and didnt see it).

ive been to the gym for nearly 2 years before covid, then had a break cuz of covid and started again bout 5 months ago. had a hypertrophy focused routine before (including sufficient nutrition etc.). while my old routine yielded results regarding strength to some extend, the increase in muscle volume has been quite slow. Which i am fine with. i have a thin/tall bodytype and because of genetics i burn calories quite fast and dont have the best muscle growth (even though my strength is not that bad compared to how thin i am). so even though i dont have much muscle growth, i do look a bit more defined and do get stronger from working out like i did before.

now, because of the experiences ive had before i want to focus more on increasing my strength further rather than increasing muscle volume, which is why im making a strength focused routine, but i need a bit of help with it. i want to make routine with a push-pull-leg 3-day-split with an additional day of cardio. i have a general plan of what exercises i should do and all of the stuff with high-intensity and low reps, explosive movement, longer rests etc..

my question is how many different exercises per split-day would you recommend, i could not find information on this anywhere (I would guess 2-4 total exercises per muscle group, but i dont know for sure). And while im here, any recommendations for good core exercises?