Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cau nuoc » cap nuoc, cac nuoc, dau nuoc
va trinh » van trinh, lap trinh, qua trinh
sach ty » sach tu, sach thu, xach tay
van cau » van dau, van hau, van chat
va tinh » may tinh
ang xa » lang xa, mang xa, dang xay
ve cua » le cua, de cua, te 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: tu ((sach ty) or (sach y)) ang xa hoi. hieu van cau nuoc ((va trinh) OR (va tinh)) ve cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) ang xa hoi. hieu van cau nuoc ((va trinh) OR (va tinh)) ve cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach y)) ang xa hoi. hieu van cau nuoc ((va trinh) OR (va tinh)) ve cua tu".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach y)) ang xa hoi. hieu van cau nuoc ((va trinh) OR (va tinh)) ve cua tu*.