Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
toc sach » hoc sach, doc sach, thuoc sach
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve nham » ve nha, ve cham
di cua » doi cua, de cua, do cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (toc sach)) ky nang xa hoi. hieu ve nham thuc dan hanh ((di cua) OR (dai cua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (toc sach)) ky nang xa hoi. hieu ve nham thuc dan hanh ((di cua) OR (dai cua)) tre~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (toc sach)) ky nang xa hoi. hieu ve nham thuc dan hanh ((di cua) OR (dai cua)) tre*.