To verify this issue follow the steps
1.create a data base and create a table 
2.then go to forms in design view and enable the "Form Design "tool bar
3.To enable this tool bar go to "view menu -->Tool bars -->Form Design".
4.In that tool bar click on the "Add Field" option, it opens a  table Assets
5.Then click on the properties, in that assign any data base and select any one of the table 
6.Then it displays data in that table, then double click on any one of the data field,  it will appear in the form

--> when we want to select any another field, it is not displaying the fields




-->But some times after on /off design mode also data is not displaying