My dad would periodically go through things but not like deep searches as far as I could tell. Like opening a drawer but not digging around, or seeing if my computer was unlocked, etc. I was also allowed a door lock though so if I really cared I would have just locked them out but it was minor enough that it wasn’t worth the potential drama to me. The area I grew up though it was very very common for parents to do forensic level dives into their kids’ rooms. Several of the people I knew in high school their bedroom doors were removed entirely by their parents. I always found that to be a gross intrusion of privacy but the Mormons never batted an eye at it