Woodland Mansion is a new type of structure that were added in Minecraft PE 1.1.0 and can be found only in the roofed forest biome. This is very rare structure and the only place to find the vindicator, evoker and vex mobs. To find the Woodland Mansion easier, you can use seed and our instructions that will lead you into it in a minute.
Create a world using our seed and in Creative mode, fly upwards and start moving into the direction illustrated below, the mansion is very close to spawn, so it won't be a problem to find it.
Seed: -396676922
Edited: 19.05.17
Reason: Changed the seed