When someone is looking for an item to buy, or exchange, there are three different places to go to, and all three recommended to use: Item auctions, to buy items for silver; item exchanges, to exchange items for other items, and the part of the forum reserved for such trade.

My suggestion is such:

Next time you will look for something to buy, you will click the dedicated link in the "Trading" section, where a blank field will appear with a question "What do you want to buy?" next to it. You will fill the field with appropriate answer: "Granite", or "GP3 puma" and press Enter or click a button next to the field itself. Upon such input you will be presented either with a list of available auctions, or a list with available exchanges, or a list with appropriate forum threads. This, I would like to think, would make things easier for both buyers and sellers.  

The option already exists to search trades and exchanges.

Instead of having separate searches for auctions, exchanges, and forums, I was thinking about having everything in a single place; or rather having a single search to do all the searching and adjusting and presenting the results accordingly.

I think it would be a case of too much coding/time needed from the devs for not enough benefit.

It might work for the auctions and exchanges (I don't know the language or existing code structure), and could be nice, but integrating the forums into a universal search is just too hard to code.