Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
duc van » duc va, duc manh, duc phan
cua cay » cua cac
ve cao » va cao, ve bao, ve cac
vi cua » vai cua, di cua

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty nang xa hoi. hieu ve cao ((duc van) OR (duc tan)) hanh vi cua cay~".
• Adding a wildcard symbol may retrieve word variants: toc sach ty nang xa hoi. hieu ve cao ((duc van) OR (duc tan)) hanh vi cua cay*.