"hadst look" is an archaic term that means "had a glance". There are several synonyms for this phrase that can be used in modern language. For instance, you could use words such as "peeped", "gazed", "glanced", "beheld" or "surveyed" to convey a similar meaning. These words all imply a quick or casual glance, but they can also suggest a more intentional or focused observation. Depending on the context in which the phrase is used, there may be other words that would be more suitable. Nonetheless, these synonyms can help to add variety and interest to your writing while still conveying the intended meaning.