There is a search box at the top of the screen. You type what you need in the box then click the search icon

BUT

Like all search engines (even Google) search results can show things you do not need, simply by virtue of what and how you typed. For example if you type in 47 mm U-bolt you may get one that is 470 mm, or a J-Bolt. That is just how searches work. And it would not show the 48 mm u-bolts which may well do the job.

If you know the product code then the above method should work just fine though

There is a better way

From the home page you will see all of our top level categories, like this:

:

So, from here click an appropriate category - lets say the fasteners because you want a bolt.

You can now use the filters down the left hand side to narrow down to the products you need

Each category has different filters. You can add more than one product per filter, so from here you could click "Bolt - Hexagon Head" and all the Hexagon head bolts will appear. You can then click back into this filter and choose Bolt-Mushroom / Coach and all the coach bolts AND hexagon bolts will appear. You can use the other filters to narrow down to size and material