Perhaps you should try some spelling variations:
vinh cuu » dinh cuu, sinh cua, dinh cu
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
duc van » duc va, duc tan, duc manh
cam duc » cam xuc, cao duc, pham duc
hieu va » lieu va, hieu qua
nang ho » nang hoc, tang ho, nang cao
nang co » nang cao, nang doc, nang noi
va cam » va cham, va cac, va cao
vi cuu » vi luu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y ((nang ho) OR (nang co)) hoi. hieu va cam duc van hanh ((vi cuu) or (vinh cuu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y ((nang ho) OR (nang co)) hoi. hieu va cam duc van hanh ((vi cuu) OR (vinh cuu)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y ((nang ho) OR (nang co)) hoi. hieu va cam duc van hanh ((vi cuu) or (vinh cuu)) tre".
• Adding a wildcard symbol may retrieve word variants: su sach y ((nang ho) OR (nang co)) hoi. hieu va cam duc van hanh ((vi cuu) or (vinh cuu)) tre*.