The three first options are indeed quite different from each other, as the items that your Pokémon will find depending on the selected option serve really different purposes. The last option is a combination of the three first ones. Do note that none of these options will bring you items which are needed to evolve some Pokémon under special conditions while holding it, like the Electrizer or the Razor Fang.
Each item does not have the same chance to be found in each category. Some are way more rare than the others.
Path for Odd-Shard Hunting!
This option will mainly bring you colored shards, that you can exchange to the Old Man in Festival Plaza for Bottle Caps.
Path for Brilliant-Stone Hunting!
This option will mainly bring you evolving stones.
Path for Rare-Treasure Hunting!
This option will mainly bring you high value items that you will be able to sell to any store.
Path for Interesting-Item Hunting!
This option is giving you the opportunity to select all the options at the same time. If you go for this one, you will get a combination of any of the items that you can get with the three other options.
(Sources: Serebii, Bulbapedia).