Perhaps you should try some spelling variations:
trinh cua » trinh luat, trinh quan, trinh luan
hieu van » hieu va, thien van, lieu va
cham duc » pham duc, cham soc, pham duy
nang hoi » nang noi, nang hoc, nang ho
tinh cua » sinh cua, tinh chat, tranh cua
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va
hoi hoi » hoi hoc, hoc hoi, hoi doi

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