Perhaps you should try some spelling variations:
dua tren » dung tren
cau tren » cu tren, dau tren, ca tren
sang mai » sang ma, sang tai, lang mai
mai khoi » mai khoa, tai khoa, cac khoi
hanh vai » hanh vi, hanh tai, hanh van
sach ky » sac ky, sach y, sach ty
hanh va » hang va, hanh vi
tu sach » thu sach, su sach, te sach
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
ky sang » ky nang, ky dang, ky tang
soc va » hoc va, loc va, doc 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 ky sang mai khoi. hieu ve cham soc va ((hanh vai) or (hanh va)) ((cau tren) or (dua tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang mai khoi. hieu ve cham soc va ((hanh vai) OR (hanh va)) ((cau tren) OR (dua tren)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang mai khoi. hieu ve cham soc va ((hanh vai) or (hanh va)) ((cau tren) or (dua tren))*.