Friends, is there a way to group multiple tabs on PRODUCT DETAILS INFORMATION SUBTAB under one? with the values in one tab... Let me know please

Do you mean on the Product Details Page, instead of several tabbed sections you'd like them all under one? SCA assigns a tab for Detailed Description, and then a separate tab for each custom rich text field you've included in the fieldset. The quick answer is that if all the information in the custom fields is appended to the native Detailed Description field, there would be only one tab. Does that answer your question?