Will moth balls keep bed bugs away?

Not really, but there are other things you can try. If you are looking for do a small area enclosed then Amvac Nuvan Strips (DDVP) can work, and sulfur candles used to be used before they outlawed them and many other things - due to health hazards - for consumer use which are more lethal to bedbugs.

1. Using a respirator and with open Windows, spray Phantom (if legal in your state), a non-repellent, relatively safe spray with long residual kill, into any size cracks within 15 feet of your bed, including ceiling and the wall area up there beginning furthest away.

Important: You do not want to repel the bugs, and in fact you want them to come near your bed to feed.

2. With a fine spray bottle filled with 70% or higher rubbing alcohol in hand, strip your bed carefully, and directly spray any bugs you see or little white eggs. Then wash bedding and all clothes nearby in hot water, AND dry them at the highest heat setting for 45 minutes or more. The drying is what kills them. Clean clothes without metal may actually be microwaved for a minute or two if watched. Then store clothes and bedding in an area far away, even outside. Small items like books can be frozen for a few hours at at least -5F degrees to kill bugs and eggs.

3. Take apart your bed and look for bugs or eggs and kill as per above any you see. Then spray Phantom or Bedlam in the seams of the mattress and cracks.

4. Pull your bed about a foot or more away from any wall place, and the legs of your bed in smooth plastic or metal cans, and sprinkle talcum powder in inside. You may also coat the legs with 4 inches of petroleum jelly.

5. Vacuum floors and discard the bag in an airtight bag. Then caulk any cracks you see within 15 feet of your bed, if possible.

6. Using a respirator, sprinkle food grade diatomaceous earth all around the bedding area, using a paint brush. And if you have no kids or pests, sprinkle Drione or Tempo 1% dust around the edges of floors.

7. Deal with the source of bugs if they are coming from somewhere else.

Note, if you live in a climate where the outside temp is below zero F day and night, then you could try ventilating the house with a fan for a week, after first turning off the water and draining the pipes. If you can get the temperature up to 130 for a few hours, Windows sealed, or over 115 steady for a couple days, that also should kill all bugs and eggs.