Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
van hanh » van thanh, ban hanh, van anh
cham luc » cham soc, nhan luc, cham cuu
hanh ve » hanh vi, hanh va, hanh kem
luc van » luoc van, luu van, duc van
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu va » hieu qua
hieu ve » hieu van
ve cau » ke cau, va cau, ve cac
x hoi » xa hoi, o hoi, x ho

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 nang x hoi. ((hieu ve) or (((hieu va) OR (lieu va)))) cham luc van hanh ve cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. ((hieu ve) OR (((hieu va) OR (lieu va)))) cham luc van hanh ve cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. ((hieu ve) or (((hieu va) OR (lieu va)))) cham luc van hanh ve cau tren".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. ((hieu ve) or (((hieu va) OR (lieu va)))) cham luc van hanh ve cau tren*.