Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
pham duy » pham duc
te sach » toc sach
kho cua » khoe cua, khi cua, cho cua
pho cua » cho cua, tho cua, ho cua
va pham » van pham, va phat, va phap
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
sach v » sach va, sach y, sach 2
duy va » duy vat, duy van, day va
v nang » va nang, vu nang, van nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach v nang ((xa hoi) or (mai hoi)). hieu va pham duy va thanh ((pho cua) OR (kho cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach v nang ((xa hoi) OR (mai hoi)). hieu va pham duy va thanh ((pho cua) OR (kho cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach v nang ((xa hoi) or (mai hoi)). hieu va pham duy va thanh ((pho cua) OR (kho cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach v nang ((xa hoi) or (mai hoi)). hieu va pham duy va thanh ((pho cua) OR (kho cua)) tre*.