The difference between tags in bilingual documents and tm files

Hello everybody

I want to get a collection of matchresult with a sdltm file by the api method, which provides two parameters such as the source egment and the sdltm file. 

Then i got some fuzzy match segmentpairs which contains a match of 95%~99%. But, according to my observation, The tagID in my source segment is very different

from that in the match segmentpairs, and None tagID of the match segmentpairs even appear in the sdlxiff file which contains my source segment. 

I would like to know how to match the source segment's tags to the tm's tags.

Thank you

Best Regards

Bradley