Perhaps you should try some spelling variations:
heats » heath, seats, beats, heads
cheats » cheath, cseats, cbeats, cheads, cheaps, wheats, chats
heat » head
cheat » chead, cheap, wheat, chat
cheads » aheads, chears, cheaps, cleads
heads » leads

Try widening your search to All Fields.

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

• If you are trying to use Boolean operators, they must be ALL CAPS: "((heats OR heat) OR (((cheads OR heads) OR (cheats OR cheat)) OR cheat)) of mixing AND (solution" or solutions").
• Removing quotes may allow a broader search: ((heats or heat) or (((cheads or heads) or (cheats or cheat)) or cheat)) of mixing and (solution or solutions ).
• Adding a wildcard symbol may retrieve word variants: "((heats or heat) or (((cheads or heads) or (cheats or cheat)) or cheat)) of mixing and (solution" or solutions")*.