Perhaps you should try some spelling variations:
kho tang » cao tang
cau tre » cau tren, cau treo, cau tra
hanh de » hanh ve, hanh kem
hieu va » lieu va, hieu qua
ky tang » ky nang, ky dang, ky trong
va cau » van cau, va cac, va dau
luc va » tuc va, loc va
de cau » ke cau, le cau, ve cau
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 tang) OR (kho tang)) xa hoi. hieu va cau ((luc va) or (duc va)) hanh de cau tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu dan ((ky tang) OR (kho tang)) xa hoi. hieu va cau ((luc va) OR (duc va)) hanh de cau tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu dan ((ky tang) OR (kho tang)) xa hoi. hieu va cau ((luc va) or (duc va)) hanh de cau tre".
• Adding a wildcard symbol may retrieve word variants: tu dan ((ky tang) OR (kho tang)) xa hoi. hieu va cau ((luc va) or (duc va)) hanh de cau tre*.