Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
cau tren » cu tren, dau tren, ca tren
hoi nang » hoi lang, ho nang, hoa nang
sach hoi » sach doi, sach moi, cach thoi
tu sach » thu sach, su sach, te sach
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
nang ma » tang ma, sang ma, nang cao
tuc va » thuc va, truc va, tuc xa
ma hoi » mai hoi, xa hoi, ma hoa
xuc va » duc va, luc va, xac va

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 hoi nang ma hoi. hieu vu cham ((xuc va) or (tuc va)) ((thanh van) or (hanh vi)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoi nang ma hoi. hieu vu cham ((xuc va) OR (tuc va)) ((thanh van) OR (hanh vi)) cau tren.
• Adding a wildcard symbol may retrieve word variants: tu sach hoi nang ma hoi. hieu vu cham ((xuc va) or (tuc va)) ((thanh van) or (hanh vi)) cau tren*.