Why the rice is in high price when there is a lot of output produce by the farmers?

Like all agricultural items Rice prices do go up due to demand and the pitfalls of agriculture pending weather/climate/disease/Pest destruction.

One primary example is pest damage about every 10yrs as rice yields hit a all time high so do common marsh rats in the Mekong delta of Vietnam. Drought plays a role as at certain times rice requires some flooding irrigation while too much may entirely wipe out the crop.

Rice is one of the most durable and versatile food staples with extreme low water weight and ease to store and ship also increases the most valued first food commodities in the world feeding starving regions of the world. It can be modified/enriched with nutrients and the versatile enough to be low-glycemic and glutton to be boiled into a broth to feed those too weak by famine and disease that otherwise couldn't digest other food sources.

**It is one the most highly demanded food staples in the world any crop failure/loss via storage damage or increase of demand via human conflicts to stave off mass starvation due to natural disasters or man made conflicts tethers the cost even higher pending an acceleration of one or more of these issues either limiting supply or increasing demand.

**The food service industry highly values it' for diversification and versatility to meet dietary restrictions or demands for low calorie and lower cost foods source versus the higher costs of fresh meats and higher cost produce. (see related question "why rices is a commodity for caterers?")