Perhaps you should try some spelling variations:
phan quoc » han quoc, tran quoc, toan quoc
phan duoc » phan duc, nhan duoc, phan nuoc
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
hanh tai » thanh tai, hang tai, han tai
so sach » so sanh, bo sach, co sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang co » nang cao, nang doc, nang noi
cuc te » cua te, cuc thue, cuc tieu

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ty nang co hoc. hieu van ((phan duoc) OR (phan quoc)) van hanh tai cuc te~".
• Adding a wildcard symbol may retrieve word variants: so sach ty nang co hoc. hieu van ((phan duoc) OR (phan quoc)) van hanh tai cuc te*.