Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
tham xuc » tham nuoc, tham thuc, pham duc
hanh ki » hanh vi, hanh ky, hanh kien
xuc van » duc van, luc van, vuc van
tu sach » thu sach, su sach, te sach
mau hoi » cau hoi, mai hoi, mau ho
vu dang » su dang, cua dang
ki su » ky su

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 ((vu dang) OR (vu quang)) mau hoi. ((lieu va) or (hieu qua)) tham xuc van hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((vu dang) OR (vu quang)) mau hoi. ((lieu va) OR (hieu qua)) tham xuc van hanh ki su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((vu dang) OR (vu quang)) mau hoi. ((lieu va) or (hieu qua)) tham xuc van hanh ki su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((vu dang) OR (vu quang)) mau hoi. ((lieu va) or (hieu qua)) tham xuc van hanh ki su triet*.