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I have a problem while in preview mode. It cuts my obj at different angles when I'm rotating around it.
Also sometimes when I rotate around whole obj selected in Edit mode, everything disappears.
Your mesh seems to be severely corrupted and causing all manner of issues and unexpected behavior, including rendering artifacts and badly computed center for rotating view in Edit Mode.
To clean it up select you object, enter Edit Mode, make sure you are in Vertex Selection mode, and switch to Wireframe shading mode.
Select all vertex with Border Select operator (do not use the A Select All operator) then hit P to separate it into a new object.
If you switch back to Object Mode you should now have to objects, a new one containing the actual geometry, and a second one with what appears to be loose edges.
Erase the loose edges and and it should fix your issue.
Render
Previews