Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
vien cac » vien bach, vien dai, vien da
gian cac » gian dan, gian cua
hang tai » hang va, dung tai
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
va hang » van hang, va nang, va lang
tai cua » thai cua, tai cuc, tri cua
tac va » tac da, tac xa, tuc va
cua te » cua tu
hien » bien, tien, dien

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang ma hoa. hieu ((((vien cac) or (gian cac))) or (hien dai)) tac va hang tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ma hoa. hieu ((((vien cac) OR (gian cac))) OR (hien dai)) tac va hang tai cua te.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ma hoa. hieu ((((vien cac) or (gian cac))) or (hien dai)) tac va hang tai cua te*.