Perhaps you should try some spelling variations:
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
hanh trinh » canh tranh, hanh chinh
trong hach » trong mach, trong cach, trong hanh
trinh qua » trinh quan, trinh cua, trinh quang
qua dung » quang dung, su dung, qua song
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sang) OR (chieu sang)) - hanh trinh qua dung trong hach ((toan cau) or (van ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu sang)) - hanh trinh qua dung trong hach ((toan cau) OR (van ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (chieu sang)) - hanh trinh qua dung trong hach ((toan cau) or (van ban))".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (chieu sang)) - hanh trinh qua dung trong hach ((toan cau) or (van ban))*.