Do 向 and 学 or 学习 work together here？ I'm not sure how to interpret 向学 in these 2 sentences。I think that 向 and 学/学习 work together.

1) 小张一心向学,厉志要成为一名科学家。'一心向学' = 1 mind to study = single-mindedly (to) study??

1) is from iciba and they give the translation as: Xiao Zhang works very hard to be a scientist.  

2) 最后搬到了学校附近，看到孟子向有礼貌的人学习礼仪，他的妈妈才满意。

看到孟子向有礼貌的人学习礼仪 = see Mengzi from have manners people learn etiquette = saw that Mengzi was learning etiquette from people with good manners

Do 向, 学习 work together? 

I seem to have 2 different meanings in English 1) to study and in 2) learn from.
1) 一心向学, means single-mindedly study. Here, 向 means 'towards', or 'head for', or 'point to'. 学 is a noun here, means 'study'. The phrase is a Chinese Idiom (成语), and the usage is kind of classic Chinese (文言), a little different and simplified from the modern usage. 

2) 向有礼貌的人学习礼仪. 向 somebody 学习 something, means learn something from somebody. 向 means 'towards' here too. The meaning is like, turn to somebody, and you learn something (from him).

Sorry for my poor English and I wish I made that clear.