What are the best supplications a pilgrim performing Umrah in Ramadan can make to his Lord after the death of his wife?

The recommended supplications (adhkar) for 'Umrah (definition) are mentioned in Fatwas no. 44090 and 31635. It is advisable to purchase Imam An-Nawawi's book "Al-Adhkar" and read from it frequently. The pilgrim performing 'Umrah should make supplications as Allah enables him, whether they are transmitted (ma'thur) or other supplications, based on the Almighty's saying: "Invoke your Lord with humility and in secret." [Al-A'raf: 55]. Indeed, supplicating with what is in one's heart may lead to deeper reflection, unlike being preoccupied with merely following words without contemplating their meanings. To know the description of 'Umrah, please refer to Fatwa (definition) no. 41476.