I want better

Research:
Do your market research. Find out what is in demand and build it. If you just build things randomly then your sales will be just as random, if any.

Quality:
Judging by your work you are quite new to 3D. Spend 1-2 years building basic props, make them as realistic as possible. Study materials, lighting, composition. Once you do this do a render and show a friend, ask which one is 3D, if they can tell you are ready to build more complex things.

Technical:
None of your models have information about UV layouts, Topology, PBR, Polygon/Vertex counts, Texture sizes etc. As a customer I would be very concerned about these details since you claim to offer GLB for real-time, however I can see your obj/gltf/3ds/fbx file are all the exact same size. This tells me you do not understand optimization or how to package content for professional delivery. One of your GLB files is 52mb in size, this is not real-time ready.

Description:
One of your descriptions is: "i did it in three days files: (glb gltf) max fbx obj". This does not help your customer with anything, they are not impressed with how long it takes you to do anything. Being fast does not bring you more customers. What they want is details, dimensions, file formats, units, compatible native software, unique details, texture sizes, material types, optionally brand names etc.

More Customers:
Check the highest selling items in the store. Match their quality at a minimum. Show more renders. Show wireframes. Do professional camera angles and lighting. Increased quality & market demand = more sales. So do your research, build 100 more models, then throw out 80 of them. If that last 20 are any good sell those. If they aren't, throw them out too and start again.

Specify what genres.

fantasy!

In addition to the good advice from 3DCargo, I would say you should change how you render and present you models.

The background should not take any focus from the object you want to sell. Use a simple background as possible, with just enough shadows and depht so it can give the customer a sense off room wheirin you objects exist. Don't let it hang free in an empty space, but don't let the background take away any attention neither.

Ex in "The Bed of the Poor" it's the bed you are selling not the rocky ground it stand on or the background image of a landscape, so there is no reason to show these things.

But if you absolute will show you models with a detailed backgroun, then do it with a more naturral enviroment. F.ex. put the bed in a bedroom, the electric pole on the ground and not above the clouds, and so on.

So always keep focus on what you are selling and avoid making the renders to much dark.