Query Builder generated SQL wrong statement (4269076)

QUESTION:
User on Query Builder, put a lookup table A first then connected to a main table B it created a query with from table A left outer join table B also with where clause looking up in small table A first.
When he added a new table C to diagram also join to the same keys of A and B. The SQL statement changed from table B left outer join table C and right outer join table A. This cause the sql running a long time because table B has many rows. See webex recording
User wanted to know any way to force it looking up table B first.