Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam quoc » nam duoc, nam buoc, nam thuoc
quoc ban » quoc bao, quoc lan, quoc quan
ban hanh » ban hang
sach tu » sach thu, cach tu, sach uu
sach ty » sach y, sach thu, xach tay
nang xa » nang x, lang xa, nang ma
vai cua » dai cua, hai cua, lai cua
vi 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: tu ((sach tu) or (sach ty)) nang xa hoi. hieu van nam quoc ban hanh ((vi cua) OR (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach tu) OR (sach ty)) nang xa hoi. hieu van nam quoc ban hanh ((vi cua) OR (vai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach tu) or (sach ty)) nang xa hoi. hieu van nam quoc ban hanh ((vi cua) OR (vai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach tu) or (sach ty)) nang xa hoi. hieu van nam quoc ban hanh ((vi cua) OR (vai cua)) tre*.