Indeed they can,if the hard drive is not encrypted,which is why i started with Veracrypt and pointed out that it's OpenSource(meaning it can't be bought by ISP's and/or agencies to leak information).They will never open my PHYSICAL Desktop even if im behind bars,or NASA gets involved,it simply wont work without a usb flash drive that holds an encrypted bitlocked key 600 megabytes of encryption worth...It will take them months and thousands lol...
Back to reality,i recocmend cyberghost because i have a cracked version of it (AAARRRRR!!!) and it works like a charm(Besides the torrenting which i don't need to hide where i am so i don't use it)