Ten-year yields have fallen to quite a low level as the concern over a U.S. economic slowdown has grown.

Investors feel there is no need to aggressively buy bonds now as yields may continue climbing amid signs of solid economic growth.

I expect bonds to keep rising. Economic growth is facing obstacles.

There is a solid demand for long-term bonds with a 20- to 30-year maturity. Twenty-year yields around 2.2 percent are attractive.

A decline in stocks is giving a boost to bonds.

There's constant demand for longer debt from pension funds and other investors who follow the index.