Portfolio search option along with filters is possible? Menu highlight in single

Hi,

1. Can we include search option inside portfolio grid along with filters, we need both options together?
2. Is there a way to turn off the display of that category/filter on the presentation side so that we can limit what is shown as a filter even though the content is still tagged – this is to limit the number of categories displayed if there are too many?
3. Also we are using single page option we need to highlight the particular menu when user scroll through the corresponding section, is it possible to set?

thanks in advance