I'll answer these questions with reference to your wife's application:
@Bryanna 2 questions
1) Does the previous TRV refusal matters on the new TRV application, specially when there is a change in "Purpose of visit" and the maritial status? in CIC website they recommend to apply again when there is change is status.
Applying too many times can negatively impact future visa applications. But, that's not the case here.
A previous TRV refusal will impact new applications if:
1. There is a dramatic shift in the purpose of visit and other factual details, or
2. If there is misrepresentation
Again, this is not really the case here. It is expected that your wife would like to be with you. However, like we've said earlier, she should not have applied for a TRV.
2) in TRV Does the host travel history matters for the guest application , specially when the host and guest are married?
Yes, it does. If for example, the host traveled/met the spouse quite recently in another country then the visa officer may not believe there's the need to meet again so quickly (specifically through a TRV app)