There is not much information provided to answer the question to the point.
Since, you are saying, no values returned, I believe you have data in the tables which match the clauses supplied in the query. But without details of tables, just by looking at the query nobody can guess the cause. However, the below join
tblQuestionnaire.quesID=tblQuestionnaireSub.qsTPRID
left side looks doubtful considering you have tblQuestionnaire.quesTPRID column. Shouldnt it be
tblQuestionnaire.quesTPRID =tblQuestionnaireSub.qsTPRID
Hope that helps.
Milind