the government should focus more its attention on increasing people’s happiness 和 the government should focus more its attention on people’s happiness 有什么区别？如果难以说明的话，请教我一下例句。

Basically it has similar meaning
The difference is increasing mean there is any standard or indicator that show the rate of people's happiness, and government have to make the results become better nowdays or in the future from the past.
While "the government should focus more its attention on people's happiness" only show government have to more concerns on that matter