Porcelain ware will never look its best if it's streaked and stained. Here's how to do basic maintenance.
Hand wash painted or decorated porcelain surfaces with a very mild dish detergent. Rinse in warm water; hand dry with a soft towel.
Use an all-purpose kitchen or bathroom cleaner for plain, more resilient surfaces such as toilets and sinks. Take a scrub brush to stains; rinse with warm water.
Use a very mild abrasive cleaner and scrub sponge as a last resort for particularly persistent stains, scrubbing only the affected area; rinse with warm water.