Perhaps you should try some spelling variations:
vien hanh » vien thanh, hien hanh, nien hanh
hieu vien » hieu hien, hieu viec, thieu nien
cau treo » cau theo, cau tren, cau triet
cay phoi » cap phoi, tay hoi, cay cho
xay hoi » xa hoi, tay hoi, gay thoi
ky dang » ky danh
phuc va » phuc vu, thuc va, chuc va
va tinh » may tinh
tinh va » tich va, trinh van, trinh vat
tu sach » thu sach, su sach, te sach
va cau » van cau, va cac, va dau

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 ((ky dang) or (ky nang)) ((xay hoi) OR (cay phoi)). hieu vien hanh phuc va tinh va cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky dang) OR (ky nang)) ((xay hoi) OR (cay phoi)). hieu vien hanh phuc va tinh va cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky dang) or (ky nang)) ((xay hoi) OR (cay phoi)). hieu vien hanh phuc va tinh va cau treo".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky dang) or (ky nang)) ((xay hoi) OR (cay phoi)). hieu vien hanh phuc va tinh va cau treo*.