Query to search table that has many in another table

Rails
1

i have 3 tables

ITEMS
id
name
…

COMPOUNDS has many compound_materials
id
item_id
…

COMPOUND_MATERIALS belongs to compounds
id
item_id
compound_id
…

i am trying to do a search to find all compounds or compounds that have
commpound materials that match a search for name

here is what i want to do but it i think i need some help. i’m not sure
if this is even possible without doing multiple queries

class Compound < ActiveRecord::Base

def name
  item.name
end

def self.search(search, page)
        paginate :per_page => 100, :page => page,
       :include => [:item, :compound_materials]
       :conditions => ['name like ? OR compound_materials.item.name

like ?', “%#{search}%”, “%#{search}%”],
:order => ‘name’
end
end

can someone point me in the right direction? thanks!

here is a link to my site so you can see what i mean:

http://wl.kuliksco.com/compounds

2

i forgot to mention that compounds and compound_materials both belong to
items

and here is the code from my compounds controller

@compounds = Compound.search(params[:search], params[:page])