1、想买
in the market for 想买，积极物色 People are always in the market for something new and different. 人们总想买点新奇的且与众不同的东西。
2、想购买
...general merchandise 杂货in the market for 想购买assure sb of sth 向某人保证某事 ...
3、想要
... an arm and a leg 非常昂贵 in the market for 想要、准备买 for the time being 目前 ...
4、想要购买
... In stock 有存货 In the market for 想要购买 In the foreseeable future 在短期内，不久 ...