Yaki,
To set the number of data points that you are viewing in a graph you need to set the X axis min and max. This gives you the range of data that you are displaying.
There are a set of functions to do this on the library, go to "User Interface>>Controls/Graphs/Strip Charts>>Graphs and Strip Charts>>Axis scaling". The function SetAxisRange can help you define the number of points in the graph display.
I hope this helps.
Regards,
Juan Carlos
N.I.