Perhaps you should try some spelling variations:
trinh viet » trinh vat
ninh viet » sinh vien, anh viet
sach ty » sach tu, sach thu, xach tay
xang xa » lang xa, mang xa, ang xa
hieu va » lieu va, hieu qua
xuc van » duc van, luc van, vuc van
va cam » va cham, va cac, va cao
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: vu ((sach ty) OR (sach y)) xang xa hoi. hieu va cam xuc van ((trinh viet) or (ninh viet)) cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((sach ty) OR (sach y)) xang xa hoi. hieu va cam xuc van ((trinh viet) OR (ninh viet)) cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((sach ty) OR (sach y)) xang xa hoi. hieu va cam xuc van ((trinh viet) or (ninh viet)) cua tu".
• Adding a wildcard symbol may retrieve word variants: vu ((sach ty) OR (sach y)) xang xa hoi. hieu va cam xuc van ((trinh viet) or (ninh viet)) cua tu*.