vbtab in reporting services 2008 expression

i am trying to use tabs in reporting service 2008 expression on a particular textbox.

i have tried using three tabs (& vbTab & vbTab & vbTab &) between field name and value for two fields.

=iif(Trim(Fields!Field1.Value) <>"","FVE1:" & vbTab & vbTab & Fields!Field1.Value & VbCrLf,"") 
& iif(Trim(Fields!Field2.Value) <>"","RV:" & vbTab & vbTab & Fields!Field2.Value,"" ) 

what i am trying to aceive is some thing like this (aligned one below the other)

FEV1:   3.29 
RV:     0.51 

But i am unable to achieve this insted it get like below

FEV1:   3.29 
RV:   0.51 

any help will be much appeiciated.

thanks