Union Government
(1) The Council of States shall not be subject to dissolution, but as nearly as possible one-third of its members retire every second year as Parliament provides by law. (2) The House of the People, unless sooner dissolved, continues for five years from the date appointed for its first meeting, and no longer - though this period may be extended by up to one year at a time by Parliament while a Proclamation of Emergency is in operation, subject to an outer limit.
The Rajya Sabha is a permanent body that never fully dissolves - about a third of its members retire and are replaced every two years, giving it continuity. The Lok Sabha, by contrast, has a fixed five-year term and can be dissolved earlier (for a fresh general election), though its term can be extended during a national Emergency.
This is why the Rajya Sabha is often called a "permanent House" - unlike the Lok Sabha, which is fully re-elected every five years (or sooner if dissolved), the Rajya Sabha is never completely reconstituted at once.