Your husband's problems are too vague to say if his problems are from the Thyroid. If his tests are within normal limits, check his diet. Does he consume iodine? Dietary iodine is from iodized table salt (not packaged salty foods or ham), cold water fish (not tuna or canned fish), or by eating a supplement of kelp. Iodine "feeds" the Thyroid. Without iodine, the Thyroid doesn't work efficiently. You could also have the doctor order a Thyroid ultrasound to further check for Thyroid health. hope this helps.
You may want your physician to order a Thyroid Cascade test to be performed. This blood test is not given to people with diagnosed Thyroid disorders, but to people with blood tests that are within normal limits, but on the low or high end of the normal scale. It is considered definitive for low level Thyroid disorders undiagnosed by the normal T-3/T-4 testing.