Perhaps you should try some spelling variations:
cai tren » cai tien, ca tren, cau tren
caim luc » cau luc
hanh va » hang va, hanh vi
hanh ve » hanh vi, hanh kem
hieu ve » hieu va, hieu van
ve caim » ve cai, ve chim
lang xa » lang ha, dang xay, lang van
dan ky » van ky
luc va » duc va, tuc va, loc va
tu dan » tuc dan, tu ban, cu dan

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu dan ky ((lang xa) or (nang x)) hoi. hieu ve caim luc va ((hanh ve) OR (hanh va)) cai tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu dan ky ((lang xa) OR (nang x)) hoi. hieu ve caim luc va ((hanh ve) OR (hanh va)) cai tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu dan ky ((lang xa) or (nang x)) hoi. hieu ve caim luc va ((hanh ve) OR (hanh va)) cai tren*".