You can drag and drop as many as you need from the Titles browser.
If you are dropping the titles on a film clip, it can be helpful to split the clip so that there is a separate clip for each title. You can do this by dragging to select the length you need for the title. Then right-click inside the yellow border and choose SPLIT CLIP. Do this for all you need. Then you can easily drag titles on the split clips. Although the clips are split, they will still play as one long clip when you share the movie.
If you just need plain titles over a background, you can just drag the titles and drop them in between other titles.