Most "bounces" on tricycle-gear airplanes are caused by landing with the nosewheel hitting the runway slightly before the mains. The drives the nose up, and the plane goes up, too. If you land main wheels first, the nose will lower, and the model will "stick". Too many modelers land too fast, which causes the nosewheel to touch first. This is noticed on hard-surfaced runways. On grass, you'll likely not see the bounce unless you are landing 'way too fast.

Very likely, you're doing the same thing. Take the model up high and see how slowly you can fly it before it stalls. Find out which elevator trim setting will give you a nice, slow glide, but still very controllable. This is your landing approach speed. It also allows you to adjust the glideslope with throttle instead of using the elevator to control the slope. Then, when you near the threshold of the runway, just cut the throttle, and ease the aircraft into a nose-high position. You should be able to touch down with the nosegear off the pavement. With some practice, you can actually hold the nose off the pavement for quite a while before the model's slowed enough that it just drops. On grass, the nose will come down instantly, due to the braking effect of the grass.