how can i apply further details to a model with out using alpha brushes
any tutorials plezzzzzzzz help me 
thanx
The Standard Brush doesn’t use an alpha - select it in the Brush palette. Alternatively, click the large ‘Current Alpha’ thumbnail on the left of your screen and then select ‘Alpha Off’ from the pop-up (this will mean that the alpha is removed from whichever sculpting brush you have selected). If you’re on a Mac you can reset all brushes by pressing the button at the bottom of the Brush palette.
thanx can i use displacement maps to creat the wrinkles
How did you mean? Do you want to use a displacement map with a sculpting brush? All you need to do is import it into the Alpha palette and then add it to the brush of your choice.
yes but we have to divide our mesh several times i want to make sharp wrinkles with out dividing much more times my maximum subdivition level is 4
Displacement maps are a render time effect, primarily used by apps like Maya to avoid the overhead of handling millions of polygons. In ZBrush, although you can displace a model using a displacement map, you still need to add geometry to do it.
Consider splitting your model into subtools. Each subtool is treated as a separate mesh and so you can divide up to your system’s limit. See here: http://www.zbrush.info/docs/index.php/Subtools
thanx for the support;);)