Perhaps you should try some spelling variations:
gian cua » gian xu, ban cua
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
van cai » van hai, van chi, van cau
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
va cua » va chua, via cua, ca cua
o cao » o lao, o cac
o ca » o cac, ho ca, o 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 ty nang xa hoi. hieu van cai ((o ca) OR (o cao)) dao ((va cua) or (gian cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. hieu van cai ((o ca) OR (o cao)) dao ((va cua) OR (gian cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. hieu van cai ((o ca) OR (o cao)) dao ((va cua) or (gian cua)) tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. hieu van cai ((o ca) OR (o cao)) dao ((va cua) or (gian cua)) tre*.