Holy ****, that law of attraction stuff is legit. Here's some possible science as to why it could work (my own personal theory anyway, so it means absolute **** to anyone who has a degree in anything having to do with this):
So everything is essentially energy. EVERYTHING. You, your clothes, even the air (because matter is basically one form of energy), even the nothingness in space is a form of energy/matter (it is called dark energy or dark matter). Well, if everything is a form of energy, then wouldn't it be possible that even your thoughts are too? Using the Law of Conservation of Energy, energy cannot be created or destroyed, only transferred and/or transformed from one form to the next. Well in quantum physics, subatomic particles seem to appear and reappear from seemingly nothing at all. Why is this despite the Law of Conservation of Energy? Well, (again it's my own personal theory so take whatever I say with a grain of salt) I believe that it's because matter is converted from dark matter (dark energy) into matter (another form of energy).
Now using what we know from the above, it would make sense that our thoughts are converted into some other form of energy. If we think about seeing yellow cars a lot, then perhaps it is because you were thinking about yellow cars to begin with. And when your thoughts converted into energy again and dispersed throughout the universe, it may have bounced back to all the other yellow cars and people/things having to do with yellow cars, because the energy that left your thoughts had to deal with yellow cars. And now, the energy of you seeing yellow cars a lot simply transferred over into making yellow cars come to you, for you to see them, again. It's really complicated and hard to explain, but I hope you get the gist of it.
There's also a second part to it, and this relates to women, and just people around you in general:
Your heart (and brain too, for that matter. Though the heart's is stronger) emit an electromagnetic field around you, because the heart uses electrical impulses as signals for contraction and whatnot. Well, it is observed that the heart reacts to our emotions. How hard, how often, its retraction rate, etc is somewhat determined by our emotions. This electromagnetic field can be detected by other people's hearts and their brains as well (although it is very small and underlying, it is there nonetheless). Now because your emotions do affect your heart somewhat, it would thus have to affect your heart's electromagnetic field (and your brain's EM field as well because it also senses your emotions too). This field radiates several feet outward, and as such people can subconsciously detect your EM field the same how you detect theirs (and as such, can alter their mood). It sort of explains how you can suddenly tell if someone is coming up behind you sometimes even though you didn't see them yet. If you are truly happy around someone, they tend to be happy as well (hence a baby's smile or laughter). Now if we can learn to truly love ourselves and have it resonate towards other people, then perhaps they can love us just the same. And perhaps if we can learn to truly love life and resonate it towards others, then we can have them love us for making them love life just the same.