This refers to the Arabic term Al-Thamyl (often spelled Al-Tamyl or associated with specific texts). In the context of Maliki literature, searchers are often looking for the famous commentary or the foundational text regarding the Mukhtasar of Khalil. However, the most likely intended text when searching for "Thamyl" in a general sense is often a phonetic variation of "Al-Tamhid" (by Ibn Abd al-Barr) or more likely, a search for the phrase "Tamyl" (reading/reciting) in the context of prayer.
كتاب معاصر يتميز بترتيبه المنطقي وسهولة لغته، وهو مثالي لمن يبحث عن إجابات سريعة ومبسطة. thmyl-ktab-fqh-alslah-al-almdhhb-almalky-pdf
by Ibn ‘Abd al-Barr