'This guy has certain list of skills' or 'This guy has specific list of skills'
Neither of these are expressed as well as it could be. Both would require the indefinite article to be grammatical (“a certain list”, “a specific list”).
I would suggest:
- This guy has certain skills.
- This guy has a specific skill-set (or specific skills).
A “list” of skills is not a common expression, and "set" is more usual, however neither is really necessary to convey the meaning desired (even if an applicant provided an actual list).
Specific is more likely to be a positive evaluation, especially in the sense that the skills he has match those that you are seeking.
"This guy has certain skills." is sometimes used to imply that, while he has some useful (relevant) skills, the set of skills might be limited or insufficient for your needs, and would often be followed by but or however.