From gamechup.com - In Fallout 4, finding bobbleheads will grant you specific bonuses for your character which range from basic stats to perks. Finding them all will also get you two trophies which is required for platinum.
Some of these bobbleheads are in obscure locations so this guide will come in handy. We recommend you to get the stats bobblehead first which will make your character a lot stronger. Also make sure to have a bunch of stimpacks and stealthboys on you. Engaging with the enemy is not recommended unless you are of a decent level. Stealthboy comes in handy if you just want to grab the bobblehead and run without anyone noticing you.
It’s also required to have maximum lockpicking and hacking ability since some of these bobbleheads are behind doors that require specific skills.