Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
hieu va » lieu va, hieu qua
hanh va » hang va, hanh vi
tuc van » thuc van, truc van, tuc va
cam tuc » cam xuc, cam tu, nam thuc
tu sach » thu sach, su sach, te sach
hieu ve » hieu van
nang xa » lang xa, nang ma, mang xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y ((nang xa) OR (nang x)) hoi. ((hieu ve) or (hieu va)) cam tuc van hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (nang x)) hoi. ((hieu ve) OR (hieu va)) cam tuc van hanh va su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang xa) OR (nang x)) hoi. ((hieu ve) or (hieu va)) cam tuc van hanh va su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) OR (nang x)) hoi. ((hieu ve) or (hieu va)) cam tuc van hanh va su triet*.