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
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
tuc dan » thuc dan, thuc day, tung dan
hieu ve » hieu van
lang xa » lang ha, dang xay, lang van
dan ky » van ky
luc va » duc va, tuc va, loc va
va cai » va cac, va bai, va dai

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

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