I'm such a novice at SEO but I'll try my best. Make sure that your tags occur in your title. Phrases are best. You have 'men' a lot in your tags, but not in your title. Pack the titles full of key phrases, and vary them slightly between your listings. Start some with 'handmade', some with 'leather,' some with 'men', some with 'messenger'...ect...
Maybe something like "Men's Leather Overnight bag, Large Cross Body Messenger and Duffel Bag, Handmade (Color) Leather Luggage"
It's totally awesome that it's stitched by hand, but I doubt people will google/Etsy search "sewn with a needle and thread".
The description was a little hard for me to read. Maybe use some spaces or colors to make it more clear and concise. I'd like to know the other dimensions, too.
https://www.etsy.com/listing/104113094/handmade-leather-travel-bag-overnight?ref=shop_home_active Bags and Purses
Messenger
Men
leather weekender
mens leather bag
mens leather duffle
mens carry on bag
mens overnight bag
handmade leather bag
mens weekender
mens luggage
bags and carryalls
men carryalls
bags and purses
messenger
men
I would try these sorts of tags: (just ideas, check to see what is being searched for)
mens leather bag
mens overnight bag
mens messenger bag
handmade leather bag
leather duffel bag
weekender leather bag
cross body leather bag
mens leather luggage
fathers day ideas
travel bag for men
hand sewn leather bag
large leather duffel
carryon travel bag
beautiful bags! best of luck to you!