Sant Baba Gurbachan Singh Jee Bhindranwale learnt the following scriptures

Sri Guru Granth Sahib Ji Maharaaj
Sri Dasam Granth Sahib
Sri Sarbloh Granth Sahib
Panj Granthi
21 Vars
Bhagat Bani
Das Granthi,and memorised the 5 morning Nitnem Prayers
Sanskrit language
Ramayan
Mahabharat
Yoga Vishest
Vedic Granthsridkoth
Teeka of Sri Guru Granth Sahib Jee, authored by 52 Nirmala intellectuals
Bhai Gurdas Jee’s Vaars
Kabit Svayas
Bhai Nand Lal Jee’s writings
Sri Guru Panth Parkash
Sri Gur Bilaas – 6th & 10th Guru and many other accepted writings
Yoga Vedant
Panj Dasee
Moksh Panth
other Granths along with which he studied Sikh History from various sources
Bhai Gurdas Diyan Vaaran’
Bhai Gurdas Kabit Svaiya
Sri Nanak Prakash
Siri Guru Pratap
Suraj Granth Parbodh
Chander Natak
Bhagat Bani
Panj Granthi
Das Granthi
Mehima Parkash
Bhavrasamrit
Sanatan Bhagawant Gita
Balmiki Ramayan
Tulsi Ramayan
Mahabharat Rig
Yujar
Sham Ved
Atharvan Ved
Gurar Puran
Yog Vashisht
Markanday Puran
Hanuman Natak
Vairag Shatak
Sarkutavali Vichar
Sagar Bavikhat Puran
Bhai Nand Lal Zindageenama
Bhai Nand Lal Gazla
Bhai Nand Lal Rubaiyat
Bhai Nand Lal Jindagee Nama
The Qu’ran
The Anjeel Parasbhag and
Masnavi Bhakh
and composed a full tika of Sri Guru Granth Sahib Jee Maharaaj

Hence why they were called Sri Maan 108 Brahm Giani Sant Baba Gurbachan Singh Jee Khalsa Bhindranvale . . . Todays katha vachicks dont even know 10% of what sant jee learnt… some get blessed by knowledge just listening to Sant Jee’s katha.