I just checked out a few of your links. You're on the right path but your current set of samples used are getting in your way. It's going to take quite a bit more production to make things sound more eerie. Right now, with the heavy focus on strings in (mostly) tonal writing - it's coming off more sad/somber than scary.
Perhaps it would be best to combine some synths or drop the strings/orchestral feel altogether. If you're intent on making it an orchestral soundtrack then I think getting some better libraries would really, really help you hit the target! Also in some cases making eerie music is less about melody (and formal song structure) and more about textures.
Check out this track:
Part of what makes it eerie is that it's NOT symmetrical and "normal" but instead unusual.
Another great reference - a bit heavier on some melodic content:
Take note of the percussion usage here. And how the strings go in and out of "tune" by playing clashing notes or doing bends.
Hope that helps!