The phrase "hadst one doubts" can be expressed using a variety of synonyms. These alternative phrases include "were uncertain," "had reservations," "lacked confidence," "suspicious," "hesitant," "unsure," "questioning," "indecisive," "uneasy," and "dubious." Each of these synonyms conveys a slightly different nuance, but all refer to a feeling of uncertainty or suspicion about something. Depending on the context, one synonym may be more appropriate than another. Ultimately, the use of synonyms can enhance the clarity and precision of communication by allowing speakers and writers to convey the intended meaning with greater accuracy.