To fix booting OS issue: I cannot boot Ubuntu16.04 installed on Lenovo's workstation D30

I cannot boot Ubuntu installed on Lenovo Workstation D30. I'd like to ask you to fix this issue. We'll have a chat and we will fix this issue together. I'll take some pictures and send you if you need then. I made a search and I found these things: 　・Some Lenovo's PCs prohibits other OS from booting 　・There is no option to make security boot disables on Lenovo's BIOS. 　・If I use Repair-boot on ubuntu, I can fix this issue. What I did: 　1. to boot Ubuntu from Live CD 　2. to install Ubuntu on a new SSD(Crucial µ≈300 525GB) 　3. to install Repair-boot and fixed as its suggestion 　4. to choose the new SSD as primary SSD on BIOS. I tried everything I could, but I cannot solve this issue. I'd appreciate your help.