It sounds like the contacts in question are on the "Phone Account," which doesn't sync to Google. You should try to export those contacts as a vCard file, then import that file into your Google account. Is the X3 that you're talking about the Nokia X3? I'm not too familiar with Windows Phone, but there should be an option somewhere to export your contacts to a vCard or CSV file. Do that, then transfer that file to your phone or computer, and then import it into Google Contacts (on the web) or into your Galaxy Trend's People app.
It sounds like the contacts in question are on the "Phone Account," which doesn't sync to Google. You should try to export those contacts as a vCard file, then import that file into your Google account. Is the X3 that you're talking about the Nokia X3? I'm not too familiar with Windows Phone, but there should be an option somewhere to export your contacts to a vCard or CSV file. Do that, then transfer that file to your phone or computer, and then import it into Google Contacts (on the web) or into your Galaxy Trend's People app.
I tried to transfer the contacts via bluetooth but it said the samsung doesn't support the service. Then I backed up contacts but it saved as NBF file. Not sure how to save it as vCard.