Perhaps you should try some spelling variations:
mai khoi » tai khoa, cac khoi, dai khoa
mai khoa » tai khoa, may khoa, dai khoa
te sach » toc sach
nang ca » nang cao, nang cap, nang cai
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
ty nang » ky nang, ty xang, ty hang
va cam » va cham, va cac, va cao
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
ca cua » co cua
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty nang ((mai khoi) or (mai khoa)). hieu va cam ((xuc va) OR (luc va)) nang ca cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ((mai khoi) OR (mai khoa)). hieu va cam ((xuc va) OR (luc va)) nang ca cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang ((mai khoi) or (mai khoa)). hieu va cam ((xuc va) OR (luc va)) nang ca cua tu".
• Adding a wildcard symbol may retrieve word variants: te sach ty nang ((mai khoi) or (mai khoa)). hieu va cam ((xuc va) OR (luc va)) nang ca cua tu*.