My walls own philosophical cracks , can this be fixed ? ...
Answers: If these are cracks that keep re-appearing because of settling or an elder house and there is no hazard or structural problems you need to use a silicone underpinning caulk so it will have some pass to it ,they make paint-able caulk merely for that reason.
If they are contemporary or one time cracks you can use drywall mud,spackle,or a latex caulk depending on how deep they are and some sand may be needed . lol
Good Luck hope this helps
Bobby
Yes, probably by a professional. You own to have it checked out, it could be subsidence.