Perhaps you should try some spelling variations:
population documentation » education documentation, population implementation, evaluation documentation
documentation methods » segmentation methods
decision aided » decision aid, decision aids, decision fixed
trees » frees
tree » free
like » life

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: population documentation methods ((((decision trees) or (decision aided))) or (decision tree)) like~.
• If you are trying to use Boolean operators, they must be ALL CAPS: population documentation methods ((((decision trees) OR (decision aided))) OR (decision tree)) like.
• Adding a wildcard symbol may retrieve word variants: population documentation methods ((((decision trees) or (decision aided))) or (decision tree)) like*.