example link :
https://www.gaytor.rent/search.php?search=-twink&cat_mode=any&c67=1&size_min=&size_max=&sortpreset=Most+seeders&orderby=seeds&sort=desc&incldead=0&view=grid

i use -twink as exact as the example, and i do search all with some category selected
but it doesnt show a single result.

i think the issue happen if your query doesnt have positive keyword, and only negative one.

i think we should be able to search only negative (if we select category or sub category)