Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
cham duc » pham duc, cham soc, pham duy
duc van » duc va, duc tan, duc manh
vu cham » va cham, vu kham, tu cham
sach ty » sach y, sach tu, sach thu
so sach » so sanh, bo sach, co sach
lang ha » long ha
nang xa » nang x, lang xa, nang ma
hieu vu » hieu va, hieu ve, hieu su
anh vi » anh va, anh ve, anh vu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ty ((nang xa) or (lang ha)) hoi. hieu vu cham duc van ((anh vi) OR (hanh vi)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ty ((nang xa) OR (lang ha)) hoi. hieu vu cham duc van ((anh vi) OR (hanh vi)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ty ((nang xa) or (lang ha)) hoi. hieu vu cham duc van ((anh vi) OR (hanh vi)) cau tren".
• Adding a wildcard symbol may retrieve word variants: so sach ty ((nang xa) or (lang ha)) hoi. hieu vu cham duc van ((anh vi) OR (hanh vi)) cau tren*.