Hi
Text, by default is placed on Track 2 at the red cursor line position. VP considers that unless you want otherwise it is to overlay the main track.
If you don't move the cursor line and add a further text ...or the cursor line passes through your first text, VP will place it on Video Track 3 etc.
If there is enough space in front of your first text and the cursor line position is suitable, a new text will also be placed on Video Track 2 otherwise it will be placed on Video Track 3
The rule of thumb is that texts clips are placed on the first available higher track at the cursor position.
The fact you had them all (apparently) on Video Track 4 was because they went their by default, the lower tracks being occupied at the cursor line position, or you played the sequence to check each one was OK, leaving the cursor line at the end and then adding the next text etc. Consequently they ended up all on the same higher Track.
Depending on the size you have for the Preview area, (controlled by dragging the horizontal white bar below it up/down) you may only be able to see two tracks when they are set at full height. To see more you can scroll the tracks up/down with the scroll bar at the right hand end or reduce the height of the tracks by clicking the Expand Track down-chevron at the extreme left of the track. The easiest way to see more tracks however is to simply drag the white bar under the preview area up as far as will go. This should enable you to see at least five tracks.
To move the texts down to a lower track (assuming there is enough space for them there) is to grab them and then drag/drop them onto the lower track in question.
This process will not create duplicates, or leave copies of the original behind.
This is Drag and Drop process NOT Copy/Paste which will duplicate.
Nat