如题,因为经常搬家,前两年的税都没有收到,不知道现在是否可以把前2年的税一起退回来,如果可以该怎么退,是否有人知道,知道的人帮个忙,谢谢了

yes, you can still file your tax return now(both personal income tax and Gst/Hst). For my understanding, you can only paper file your prior years returns now, except for 2006 return. And you probably need to provide all the related documents, for example T2202A. You can try 1-800-959-8281. Make sure to ask your Federal and provincial tution credits balance, see if these numbers are reasonable, because these numbers will affact your following years personal income tax return.
Hopely, this can help you a little bit.

One thing that I forgot to mention. When you call CRA, they will ask you some personal information. If you moving a lot, you need to figure out the addfess that you filed in your last return. If you can not tell the address that they hold on their system, believe me, they will not tell you anything.

谢谢,特别感谢,但是都需要什么文件呢,这个知道吗?

If you did not have any income in previous years (in other words, you did not pay any income tax), basically, you are claiming Gst/Hst rebate. If you are a student, the only thing that I can think about is your T2202A for you tuition credits. If you had income before any you paid some income tax, there are some expenses that you can calim in order to get you tax payment back and/or build your tax credits, such as non-reimbursed medical expenses. It really depends. Any expense that you think you may be able to claim, you should keep it. And anything that you need mail to CRA, you should keep a copy.
Here is all I know. I may be wrong. You better call CRA first, see what they are going to say.