My eyelid won't fold properly. Can it be treated without surgery? (Photo)

You have a double crease with some loss of upper lid volume. There is a hint os a mild ptosis (droopy eyelid).Surgery would correct this better that a temporary solution like a dermal filler to improve the upper lid volume. 

Unfortunately, the only permanent way to correct the
eyelid problem you are describing is with surgery. These procedures are quiet
common and can even be performed in your surgeon’s office under local
anesthesia.

I recommend scheduling a consultation with a few
different board certified facial plastic surgeons who specialize in Asian blepharoplasties.
Ask to see their before and after images and choose the surgeon who makes you
feel the most comfortable and confident. This will go a long way in your
recovery process.

In the meantime, for quick relief, you may consider using
eyelid tape.

In the mean time, you can research using tape on the internet to force a fold in the eyelid.  Many people use tape as an alternative to surgery and there are some special tape products available for this purpose as well.