Perhaps you should try some spelling variations:
vu triet » su triet, ve triet, va triet
hang lap » sang lap, hang la, hang tap
ban hang » ngan hang
vien cac » vien bach, vien dai, vien da
sach ty » sach y, sach tu, sach thu
xuc ban » duc ban, cuc ban, quoc ban
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty xang, ty hang
ve cam » ve cham, ve cac, va cam
lap vu » lap va, lap du, lap tu
x hoi » xa hoi, o hoi, 5 hoi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((x hoi) OR (x ho)). hieu ((ve cam) OR (vien cac)) xuc ban hang lap vu triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang ((x hoi) OR (x ho)). hieu ((ve cam) or (vien cac)) xuc ban hang lap vu triet~".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((x hoi) OR (x ho)). hieu ((ve cam) or (vien cac)) xuc ban hang lap vu triet*.