Are renters tied to their lease term?

[Hen Ley]

I was told that if a tenant has a life changing event (change jobs, move, etc.) during the course of their lease, it is the landlord's job to begin looking for a new tenant.  The original tenant is still held to the original lease term until the landlord finds a suitable new tenant, but the landlord is obligated to begin looking and the original tenant may be let out of their lease when the new tenant is found.  Is this accurate?