Forms :: Combo Box Value Based On Selection In Other Combo Box?

I'm trying to build a database for daily work. My work in daily basis I have to fill all condition for several items.

We have two areas, with two locations under each area, and three systems under each location and each system contain more than 500 items.

I created all tables and fill by all information:

1-Table 1: Area 1, Area 2, Area 3, Area 4, Area 5, Area 6.
2-Table 2: Location 1, Location 2.
3-Table 3: System 1, System 2, System 3.
4-Table 4: all items under System 1-1-1
5-Table 4: all items under System 1-1-2

[Code] ....

Last table will be LogBook which will be as follow:

date l time l area l location l system l item l Conition1 l Conition2 l Conition3

My question regarding to the form of the above table:

How can I make a combo box for area field and when I select for example area1 will appear only the locations which under area1 in location field, and when I select location1 for example will appear only the systems under location1 in system field, and when I select system1 one for example will appear only items under system 1.Combo box list will be based on the selection in previous combo box and so on.