Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
thanh di » thanh doi, thanh de, thanh do
vu khach » vu khanh, vu khac, vay khach
va thanh » gia thanh, ban thanh, va tinh
hieu va » lieu va, hieu qua
cao suc » cao su, cao duc
su sach » so sach, vu sach
hieu ve » hieu van
suc va » duc va, tuc va, luc va
di cau » da cau, diem cau
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (vu khach)) ky nang x hoi. ((hieu ve) OR (hieu va)) cao suc va thanh di cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu khach)) ky nang x hoi. ((hieu ve) OR (hieu va)) cao suc va thanh di cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (vu khach)) ky nang x hoi. ((hieu ve) OR (hieu va)) cao suc va thanh di cau tren".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu khach)) ky nang x hoi. ((hieu ve) OR (hieu va)) cao suc va thanh di cau tren*.