Using gf

In your vimrc

" gf goto_file, automatically add search for these file extensions
:set suffixesadd+=.v
:set suffixesadd+=.sv
:set suffixesadd+=.bh.v

Now gf on a module name will try to open file.v file.sv and file.bh.v if they are in the same folder. Another good reason to keep module and file names matching.

ctrl-6 will jump back to the previous file.