@ Saille
I tried your technique on using honey to tame white line, and guess what? it really works. now my white line seems to come to my hand every time I put mine in their enclosure. and the most terrific thing is, that they don't bite anymore.
now I can touch them and let them crawl over my hand without worrying of the bite. and for sure they don't try to get away from me. even when I accidentally squeeze/hold them to tight.
for those who interested in how I do it, please check this out:
before entering their enclosure I will prepare all the things that I need. you do need honey of course, a small bowl for the honey, a small plastic spoon or a straw that is sturdy enough to handle white line jaw. take few drops of honey with spoon or the straw with your left hand, then try to take the white line slowly with your other hand. be careful not to frighten them. when they already securely handled in one of your hand, try to feed them the honey. they'll like it, and before you know it, they already associate you with something delicious and feeding time. for first timer, I recommend to use gloves though, in case the white line get a little nervous.
anyway, big thanks to you Saille
ps. I'm getting another gecko, one pair of Gekko smithii and one pair Cyrtodactylus (though I don't know what species is it).