YOU SAID:

I have doubts in my ability to be successful

INTO JAPANESE

成功する能力に疑問がある

BACK INTO ENGLISH

I doubt my ability to succeed

INTO JAPANESE

成功する能力が疑わしい

BACK INTO ENGLISH

Suspicious ability to succeed

INTO JAPANESE

成功する疑わしい能力

BACK INTO ENGLISH

Suspicious ability to succeed