Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van tuan » van quan, van ban, anh tuan
so sach » so sanh, bo sach, co sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cao hoc » co hoc, cho hoc, chat hoc
hieu ve » hieu va
xuc van » duc van, luc van, xuc ban
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ty nang cao hoc. ((hieu ve) OR (hieu van)) cam xuc van tuan ((vi cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ty nang cao hoc. ((hieu ve) OR (hieu van)) cam xuc van tuan ((vi cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ty nang cao hoc. ((hieu ve) OR (hieu van)) cam xuc van tuan ((vi cua) or (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: so sach ty nang cao hoc. ((hieu ve) OR (hieu van)) cam xuc van tuan ((vi cua) or (dai cua)) tre*.