I want to select lines (bahnstrecken) within a polygon (bundesland). My goal is a selection shown in the following screenshot, which I did manually. Before I used two tools: I converted the polygons to lines and splitted the linies (bahnstrecken) with the new line-layer which was formerly a polygon. The result is a lines layer, which geoemtries end exactly at the polygon borders.
The problem is this: When I use different spatial query methods (intersects, contains, touches, fully contains) I never get the result I want. How can I reach the selection result shown in the first screenshot above? I think I should use the WITHIN method, but the results of the spatial selection tool appear quite strange to me: